The king, in Washington for President Barack Obama's nuclear summit, gave his warning after Israel claimed that Syria had handed over Scud missiles in its armoury to the Lebanon-based Hizbollah. His comments, which were made to a private meeting of the US Congressional Friends of Jordan caucus were said to be "sobering".

Syria yesterday denied the allegation that it has provided Hizbollah with long-range Scud missiles, which would allow them to target Israel's cities. The country's foreign ministry said the claims would be used as a pretext by Israel to raise tension prior to a possible attack on Hizbollah.

"For some time now, Israel has been running a campaign claiming that Syria has been supplying Hizbollah with Scud missiles in Lebanon," a foreign ministry statement released yesterday said. "Syria strongly denies these allegations which are an attempt by Israel to raise tensions in the region."

However, the statement did not appear to rule out an alternative possibility being raised by defence sources, that Damascus has allowed Hizbollah control of or access to Scud missiles still currently in Syria. Officials in Syria have warned that it would join in any war involving Israel, Lebanon and Hizbollah.

After a series of crushing earthquakes in the early hours of Wednesday morning, the largest being recorded by the Chinese Earthquake Administration at magnitude 7.1, a four-storey shopping centrecomplex collapsed and caught fire, incinerating most of its occupants.

Elsewhere in Jiegu, the death toll had reached 617 on Thursday, with a further 9,110 injured, 1,000 seriously. Among the dead were 66 children from three local schools. Makeshift hospitals had been set up, but medicine was still in transit on Thursday and doctors told the Chinese state media there was little they could do other than amputate.

Jiegu lies on the Tibetan plateau, more than 12 hours from the nearest major airport, but China immediately mobilised the full might of its resources, summoning rescue workers from across the country.

President Obama told delegates from 47 nations at the Nuclear Security Summit on Tuesday that it would be a "catastrophe for the world" if al-Qaeda or another terrorist group got a nuclear device, because so many lives would be lost and it would be so hard to mitigate damage from the blast.

A 10-kiloton nuclear explosion would level buildings within half a mile of ground zero, generate 900-mph winds, bathe the landscape with radiation and produce a plume of fallout that would drift for hundreds of miles, the guide says. It was posted on the Internet and sent to local officials.

The document is designed to help local officials craft plans for responding to a nuclear blast. The prospect is anything but far-fetched, says Rick Nelson of the Center for Strategic and International Studies. "Do I think in my lifetime I'll see the detonation of a nuclear device? I do."

The man who 'broke' the Bank of England (and who is still able to earn a cool $3.3 billion in a year) said the same strategy of borrowing and spending that had got us out of the Asian crisis could shunt us towards another crisis unless tough lessons are learned.

Soros, who worked as a porter to pay for his studies at the London School of Economics after emigrating from Hungary, warned us to heed the lesson that modern economics had got it wrong and that markets are not inherently stable.

"The success in bailing out the system on the previous occasion led to a superbubble, except that in 2008 we used the same methods," he told a meeting hosted by The Economist at the City of London's modern and impressive Haberdashers' Hall. "Unless we learn the lessons, that markets are inherently unstable and that stability needs to the objective of public policy, we are facing a yet larger bubble."

"We have added to the leverage by replacing private credit with sovereign credit and increasing national debt by a significant amount."

Up to 5,000 flights could have been affected by the end of Thursday. Planes have been grounded in the UK, Ireland, the Netherlands, Belgium, Denmark, Norway, Sweden and Finland. France is also preparing to close its main airports. Eurocontrol, which covers 38 nations across Europe, said the ash ejected by the volcano underneath the Eyjafjallajoekull glacier in Iceland would continue to move in a south-easterly direction.

Experts have warned that the tiny particles of rock, glass and sand contained in the ash cloud could be sufficient to jam aircraft engines. Mr Flynn, Eurocontrol's assistant head of operations, said the extent of the disruption was "greater than we've ever seen before in the EU" and warned that the problem could persist for a further 48 hours.

"The meteorological situation is such that the volcanic ash is progressing very slowly eastwards but there is not a lot of wind... so it is very slow and very dense," he told the Reuters news agency.

The restrictions silenced Heathrow airport, the world's second busiest, and stranded tens of thousands of passengers around the world. Norway, Denmark, Sweden, Belgium and the Netherlands all later shut down their airspace entirely, while there was also major disruption in Finland, France, Germany and Spain.

"We will review further Met Office information, and at 0230 BST tomorrow we will advise the arrangements that will be in place through to 1800 BST tomorrow. However, be aware that the situation cannot be said to be improving with any certainty as the forecast affected area appears to be closing in from east to west. We continue to work closely with airports, airlines, and the rest of Europe to understand and mitigate the implications of the volcanic eruption."

The statement from the Israeli prime minister's anti-terror office took the unusual step of calling on families of Israelis visiting the Sinai to establish contact with them.

The commander of the anti-terror office, Brigadier General Nitzan Nuriel, acknowledged that there had been rumors that Israelis have been kidnapped in the Sinai. "We don't work according to rumors," he Israel TV. "We work according to firm intelligence." He said it would "take some time" to disprove the rumors, which circulated all day Tuesday.

"It is very possible that at this moment, there is a terror cell that has the intention and has a plan in operation to kidnap an Israeli and bring him to Gaza," he said. Palestinian militants in Gaza have been holding an Israeli soldier captive for more than three years. In unusually strong wording, the Israeli anti-terror office called "on all Israelis residing in Sinai to leave immediately and return home. Families of Israelis residing in Sinai are asked to contact them and update them on the travel warning."

And their alleged plan ended in disaster when the Polish pilots made one final and disastrous attempt to land, killing Mr Kaczynski, his wife, and 94 others on board the plane. 'One version of events says that the plane approached the airport four times, because every time the Russians refused it permission to land - they wanted to send the plane with the president to an airport in Moscow or Minsk,' Mr Gorski claimed in an interview published in the newspaper Nasz Dziennik.

'They came up with some dubious reasons: that there was fog over the airport, and that the navigation system didn't work as it was under renovation, and that airport had a short landing strip.' The claims were made as shocking new details emerged of the final minutes of the flight before it crashed into a Russian forest on Saturday morning. One of the Russian air traffic controllers involved in the tragedy said he believes the Polish air force pilot Arkadiusz Protasiuk, 36, was under severe pressure 'to land at any cost' so that the president would not miss the commemoration of the death of 22,000 Poles slaughtered by Stalin.

But he claims there were also serious language problems between the control tower at the military airport near Smolensk and the crew as the aircraft began its descent, and final approach, 'without our permission'. The crew failed to report to the ground their altitude readings, said Colonel Anatoly Muraviev, a former pilot. He believes the captain 'was desperate to land because of the high ranking passengers he was carrying. It killed both the crew and the passengers.'

It was known that Mr Kaczynski once fired a flight crew when they refused to land at Tbilisi - and flew to another airport, he said. 'Now try to imagine yourself in chief pilot's shoes. Fear, false shame, thinking that going to another airport is a disgrace - all this led to the fact that the crew died and killed all the others. I am a former pilot myself, I understand all this very well.'

Cardinal Tarcisio Bertone had said homosexuality, not celibacy, lay behind the child sex abuse scandals. The cardinal, the Vatican's foreign minister, was speaking in Chile, where his comments were also condemned. Cardinal Bertone was attempting to defuse the scandals currently afflicting the Catholic Church, which are largely cases of priests molesting children, mainly boys, the BBC's David Willey reports from Rome. He added that some "surprising" initiatives regarding the sex abuse scandal would soon be revealed but did not elaborate.

Visiting the Chilean capital Santiago on Monday, Cardinal Bertone told a news conference: "Many psychologists, many psychiatrists have demonstrated that there is no relationship between celibacy and paedophilia but many others have demonstrated, I was told recently, that there is a relationship between homosexuality and paedophilia. That is true. I have the documents of the psychologists. That is the problem."

A Chilean communist MP, Hugo Gutierrez, told AFP news agency: "Celibacy does more damage to a human being than homosexuality, which is a freely made choice. I'm shocked by these words from a senior dignitary of the Church." Aurelio Mancuso, former president of a Italian gay rights association Arcigay, said: "The truth is that Bertone is clumsily trying to shift attention to homosexuality and away from the focus on new crimes against children that emerge every day."

Chinese TV showed wrecked buildings and people scrabbling through debris, as the government began a rescue misssion. Yushu is hundreds of miles from an airport, and it is thought rescue crews may take time to reach the quake zone. "Soldiers have been dispatched to save the people buried in the collapsed houses," local official Huang Limin was quoted as saying by China's state news agency Xinhua.

The region, which is home to ethnic Mongolians and Tibetan farmers and herdsmen, is dotted with coal, tin, lead and copper mines. China's Sichuan province, which neighbours Qinghai, suffered a huge earthquake in 2008, when thousands of schoolchildren were among the 87,000 people killed or missing. Five million people also lost their homes, and officials estimated rebuilding work would take at least three years.

The Niagara County Community College, a state university in New York, lecturer said due to the high amount of sightings every year, it should follow that students should be able to investigate phenomenon. "(A sighting) happens to millions of people (around the world)," he said. "It's about time we looked into this as a worthy area of study. It's important that the whole subject be brought out in the open and investigated."

Prof Haseley, who is also head of the Western New York Mutual UFO Network, an organisation that is focused on UFO research, said there were up to 50 UFO sightings are reported every month across region. He said the group investigated the sightings in a "scientific manner" using field investigation, radar, astronomy and meteorology. "To say we are UFO believers basically implies we are taking this on faith, and that's not the case. There's plenty of evidence," he said.

He dismissed the inevitable suggestions from skeptics that such study would be waste of time.

Some nights Albert Snyder wakes up at 3 am. Other nights he doesn't sleep at all, tormented by thoughts of the hateful signs carried by a fundamentalist church outside his Marine son's funeral.

"Thank God for Dead Soldiers."

"You're Going to Hell."

"Semper Fi Fags."

Most mourners try to ignore the taunts. But Snyder couldn't let it go. He became the first to sue the church to halt the demonstrations, and he's pursued the group farther than anyone else. His tireless efforts have drawn support from across the country, including a wave of donations after he was ordered to pay the church's court costs - a $16,500 judgment that the congregation plans to use for more protests.

Lance Corporal Matthew A Snyder, 20, was not gay. But for the Westboro church, any dead soldier is fair game. Pastor Fred Phelps oversees a congregation of 70 to 80 members - mostly his children and grandchildren. They consider themselves prophets, and they insist the nation is doomed.

Israeli diplomats attribute Mr Netanyahu's last-minute cancellation to Turkish and Egyptian plans to discuss Israel's nuclear arsenal. But his absence from an event intended to show US allies and partners rallying around the American president's agenda was, at the very least, deeply symbolic. The US-Israeli alliance, for decades the cornerstone of Middle East power politics, is in rocky shape. The Obama administration is angry about Israeli settlements in occupied East Jerusalem.

Mr Netanyahu's government is recoiling at what it depicts as Mr Obama's unreasonable demands. The tension between the two sides has become a story of personal snubs and policy differences even as the US and Israel profess their devotion to each other. As George Mitchell, Washington's Middle East envoy, prepares to return to the region, US officials are considering eventually issuing outlines of their own for an Israeli-Palestinian deal - a turn of events Israel is desperate to avoid.

One thing is clear: even as the diplomatic tensions mount, no one in Washington is questioning the American commitment to Israel's security, a pledge described by Mrs Clinton as "rock-solid, unwavering, enduring and for ever". She boasted in her Aipac speech that Washington was increasing the $3 billion military assistance the US delivers to Israel each year. Nor does the Obama administration see much scope in reducing other subsidies to Israel. All the same, some officials are looking at one possible source of pressure: eventually issuing US "parameters" or guidelines for a peace deal.

The Obama administration is, in other words, shaping a policy more nuanced than its predecessors': it seeks to blend a cast-iron commitment to Israel's security with a much more critical stance on settlement building and the peace process. As Iran continues its progress towards nuclear capability, it is a distinction that seems unlikely to disappear. For Mr Netanyahu and his government, uncomfortable times lie ahead.

But he said the so-called P5 - the five permanent members on the Security Council - should press Israel on its refusal to join the nuclear Non-Proliferation Treaty (NPT). "Let's also try to convince the P5 to bring Israel onboard. You see, you have possibly today two emerging threats" in the Middle East, Gheit told the "PBS Newshour" on US public television.

"We are eager that we do not have a nuclear Iran, as well as we do not want to see a nuclear Israel. We want a zone that is free of nuclear weapons - and it can be done," he said. Israel is widely believed to have nuclear weapons but maintains a policy of strategic ambiguity, refusing to confirm or deny its arsenal.

Iran is part of the NPT but Western powers believe it is in violation of the treaty and is pursuing nuclear weapons. The clerical regime insists it is only seeking the peaceful use of nuclear energy. Israeli Prime Minister Benjamin Netanyahu at the last minute pulled out of the Washington summit, reportedly out of concern that Arab states and Turkey would shift the focus to Israel and away from its arch-enemy Iran.

Analysts said the Dow's move above 11,000 could provide a psychological boost and perhaps draw more investors to the market. "There is a huge stockpile of cash on the sidelines earning virtually nothing," said Jack Ablin, chief investment officer at Harris Private Bank in Chicago. "Maybe this can help shake a few people into the market."

Stocks have been rising this year on growing expectations that the economy will shake off job market weakness and housing problems. A test of whether the Dow can hold the 11,000 mark will come in the next three weeks when companies report earnings. Investors also will want to see whether the government's next employment report, due in early May, shows that employers added jobs in April as they did during March.

On Monday, a loan agreement for Greece allowed US investors to focus on domestic economic and corporate news, including announcements of two big deals. Investors have been concerned that mounting debt in Greece and other European nations including Spain and Portugal would stunt a global recovery. "This is clearly a positive development that the EU is identifying and dealing with what has really been it's first real challenge," said Alan Gayle, senior investment strategist for RidgeWorth Investments.

Britain's FTSE 100 rose 0.1 percent, Germany's DAX index rose less than 0.1 percent, and France's CAC-40 slipped less than 0.1 percent. Japan's Nikkei stock average rose 0.4 percent.