Updated

As thousands of Palestinians celebrated in the West Bank and in Lebanese refugee camps, governments across the globe offered condolences to an America that looked more vulnerable than ever after Tuesday's terror attacks.

People on every continent watched in horror as astonishing images of terror in the United States filled their television screens. But in the West Bank town of Nablus, Palestinians cheered and distributed candy to passers-by, and Iraqi television played a patriotic song that began "Down with America!" as it showed the World Trade Center towers collapsing.

About 3,000 people poured into the streets of Nablus shortly after the attacks began, chanting "God is Great" and — in their traditional gesture of celebration — handed out candy.

There were no reports of celebrations elsewhere in the West Bank and Gaza.

"At this most difficult hour, Israelis stand with you ready to provide any assistance," said Israeli Prime Minister Ariel Sharon. "The government of Israel declares tomorrow a day of mourning as we bow our heads and share the pain of the American people."

Israeli Foreign Minister Shimon Peres offered the U.S. the assistance of a highly-specialized military emergency team to come and help rescue people in the demolished buildings and to provide other support functions. Israeli officials said a plane was waiting on a runway in Tel Aviv with 100 to 200 people ready to fly over if the U.S. said the word.

Sheik Ahmed Yassin, whose Islamic militant Hamas group has carried out a series of suicide bombings in Israel, said he was not interested in exporting such attacks to the United States.

"We are not ready to move our struggle outside the occupied Palestinian land. We are not prepared to open international fronts, however much we criticize the unfair American position," Yassin told reporters in Gaza City.

In Ein el-Hilweh, Lebanon's largest refugee camp, where about 75,000 Palestinians live, revelers fired weapons in the air, witnesses said. Similar celebratory gunfire was heard at the Rashidiyeh camp near the southern city of Tyre.

Palestinian leader Yasser Arafat offered his sympathy to Americans and said he was horrified by the devastating attacks, which also hit the Pentagon.

Leaders around the world — including most in the Middle East — offered messages of support.

Afghanistan's Taliban rulers condemned the attacks and rejected suggestions that suspected terrorist mastermind Usama bin Laden, who has been given asylum in Afghanistan, could be behind them.

"It is premature to level allegations against a person who is not in a position to carry out such attacks," said Abdul Salam Zaeef, the Taliban ambassador in Pakistan. "It was a well-organized plan and Osama has no such facilities."

President Gen. Pervez Musharraf of Pakistan, one of three countries that recognize the Taliban's government, condemned the attacks and called for cooperation to combat the "modern-day evil" of terrorism.

Key indexes sank on world stock markets and many European and Asian airlines canceled flights to the United States and recalled planes already in the air.

Britain and Belgium banned commercial flights over their capitals, and Britain warned its citizens traveling in the United States to beware of possible further attacks. Israel closed its airspace to foreign flights and evacuated staff from diplomatic missions and Jewish institutions around the world.

Libyan leader Moammar Gadhafi, whom the United States has accused of backing international terrorism, called the attacks "horrifying" and urged Muslim aid groups to offer help "regardless of political considerations or differences between America and the peoples of the world."

Syria's government condemned the attacks and offered condolences to the United States and the American people, the official Syrian Arab News Agency reported. Syria has also been at odds with the United States, which has accused it of backing terrorism.

Iranian President Mohammad Khatami, a moderate who is struggling for power against the country's hard-line Islamic leaders, expressed "deep regret and sympathy with the victims" and said "it is an international duty to try to undermine terrorism."

Many countries beefed up security at American embassies, and President Bush put all American military forces overseas on high alert.

Ordinary citizens offered condolences at American embassies around the world — Norwegians left bouquets of flowers in a park near the U.S. Embassy, Russians placed flowers near the Moscow mission and in Budapest, there were dozens of candles.

In Berlin, hundreds of people marched silently down Unter den Linden boulevard at nightfall to a service at the city's main cathedral to mourn the victims.

NATO called an emergency meeting of its governing council and urged an intensified war against international terrorism. "Our message to those who perpetrated these unspeakable crimes is clear: you will not get away with it," it said.

In New York, the U.N. Security Council condemned the attacks and urged all nations to work to bring the perpetrators to justice.

"It is impossible to fully comprehend the evil that would have conjured up such a cowardly and depraved assault," said Canadian Prime Minister Jean Chretien.

Russian President Vladimir Putin condemned the attacks and called them "a blatant challenge to humanity."

"This mass terrorism is the new evil in our world today," said British Prime Minister Tony Blair. "It is perpetrated by fanatics who are utterly indifferent to the sanctity of human life."

Queen Elizabeth II said she was watching developments in "growing disbelief and total shock."

Pope John Paul II condemned the "unspeakable horror" and said he was praying for the victims' souls and for their families.

While Iraqi TV appeared to salute the attacks, Modhafar Bashir, a 35-year-old poet watching the news in a Baghdad coffee shop, said he condemned such violence. "The problem is that America has created so many enemies inside and abroad," Bashir said.

China said it was "horrified" and Chinese President Jiang Zemin expressed "grave concern for the safety of Chinese in the U.S."

"This outrageous and vicious act of violence against the United States is unforgivable," said Japanese Prime Minister Junichiro Koizumi.

Arafat offered his condolences to the American people and government. "We are completely shocked. It's unbelievable," he said.

U.N. Secretary-General Kofi Annan said "there can be no doubt that these attacks are deliberate acts of terrorism, carefully planned and coordinated. ... I condemn them utterly."

Egyptian President Hosni Mubarak called the attacks "horrible and unimaginable." In Germany, Chancellor Gerhard Schroeder described them as "a declaration of war."

Malaysian Prime Minister Mahathir Mohamad Mahathir expressed sadness, but urged the U.S. government not to seek revenge.

"Retaliation will lead to the deaths of many people and will be followed by more counter-strikes," he was quoted as saying.

In the U.S. Caribbean territory of Puerto Rico, people scrambled for news of relatives and friends in New York, where an estimated 2 million Puerto Ricans live.

Groups gathered on the corners of cobble-stoned streets in San Juan, clinging to strangers in search of more details.

"Dios mio, have mercy!" exclaimed a whited-haired man, making the sign of the cross as he watched the second tower explode on TV.

Broadcasters around the world broke into programming to show images of the disasters.

"This portends the end of the world," said Ekima Ibass, a civil servant in Congo's capital, Kinshasa. "It could be the beginning of a new world war," Ibass added.

The Associated Press contributed to this report