The United Nations and several foreign aid organizations completed a swift withdrawal from Afghanistan on Thursday, fearing a U.S. strike on targets associated with Usama bin Laden, a leading suspect in the terror attacks on the United States.

A group of foreigners who left Kabul's war-ruined airport aboard three U.N. aircraft included relatives of two American aid workers who are being tried by the devout Muslim nation's hard-line Taliban rulers on charges of preaching Christianity. Six of their fellow workers — four Germans and two Australians — are also being prosecuted.

American Deborah Oddy, the mother of 24-year-old defendant Heather Mercer, held a mandatory shawl tight around her head, her eyes brimming with tears. She only had been allowed one visit with her daughter since arriving in Afghanistan on Tuesday, hours before the attacks on New York and Washington.

Heather's father, John Mercer, left very reluctantly. Until late Wednesday, he said he was determined to stay, but in the end he left along with David Donahue, consul-general of the U.S. Embassy in neighboring Pakistan. Mercer wouldn't talk as he boarded the aircraft.

Nancy Cassell, the mother of American Dayna Curry, 29, also left. She had seen her daughter five times since arriving more than two weeks ago.

Cassell and Oddy wrote farewell letters to their daughters on Wednesday. They said it was a devastating experience.

Aboard the three U.N. aircraft were about 35 international aid workers, the relatives of the detained Americans, a handful of journalists and three diplomats — including Donahue — who had been seeking information about the Taliban case against their compatriots.

The International Red Cross evacuated its nonessential staff members, saying it would continue to evaluate the safety of those who remained. All other Western aid workers are believed to have left Afghanistan.

"I don't feel well about leaving. It is unfortunate, but it is due to the situation. I cannot change it," said Helmut Landes, of the German Embassy in Pakistan. Australian diplomat Alastar Adams also left.

A Pakistani lawyer for the detained aid workers, whose trial is under way in beleaguered Kabul, was expected to arrive Saturday. The diplomats would not identify him, but he was described as an Islamic scholar and alumnus at one of the religious schools in Pakistan that many Taliban leaders have attended.

Several Arabs and their families also left. At least three families were seen heading out of Kabul, their destinations unknown.

Like the foreigners who pulled out, Afghans also feared a U.S. attack.

"If you die today or tomorrow, it is written with God. There is nothing you can do," said Mohammed Ali, a Kabul man who wondered aloud when a U.S. strike might occur. "We will just wait."

The Taliban have urged the United States not to attack, insisting bin Laden was not involved in Tuesday's onslaught. "Usama and other Arabs who are living in Afghanistan have no connection with the attacks in the United States. They are not even capable of doing these things," Taliban-run Radio Shariat said Wednesday.

The Taliban demanded to see evidence backing allegations that bin Laden runs a global terrorism network responsible for the strikes.

"We will study their evidence first. This is the first phase. The question of extradition comes later," Abdul Salam Zaeef, the Taliban's ambassador to Pakistan, said Wednesday.

Without television — banned under the severe brand of Islamic law the Taliban enforce — Afghans saw no footage of the devastation at the World Trade Center and the Pentagon. But throughout the capital, people held small transistor radios to their ears to listen to news accounts.

They heard the Pashtu- and Persian-language services of the British Broadcasting Corp. and the Voice of America. Radio Shariat quoted "foreign press reports" to inform them of the terrorist attacks.

"It's terrible. It makes me sad. No one can bear to see a country attacked," said Inayatullah, a drugstore manager who uses only one name.

"It is a very bad action on humanity," he said. "Nobody, but nobody, wants that criminal action."

Many people appeared upset that the Taliban government has protected bin Laden, who is wanted in the United States for prosecution on charges of masterminding the deadly 1998 bombings of two U.S. embassies in East Africa. Despite U.N. sanctions, the Taliban have refused to hand him over.

"Of course he should go," said Zamair Khan, a carpenter in Kabul.

The United States retaliated for the embassy attacks by sending 70 Tomahawk cruise missiles smashing into eastern Afghanistan, targeting training camps operated by bin Laden. He escaped unhurt.