The U.S. ambassador traveled to this Saudi oil-industry city Monday with a simple message for the gathered Americans: Go home. We cannot protect you.

Huddled in a meeting room in a Holiday Inn still pocked with bullet holes after the latest in a string of attacks on Westerners killed two Americans and four others, many said they would heed his words.

The first to go were among the 90 foreign employees of ABB Lummus Global Inc. (search), a Houston-based oil contractor whose offices were attacked Saturday by four gunmen trying to encourage Saudis to join the resistance against the U.S. occupation of Iraq.

The Saudi interior minister said early Tuesday that the attack appeared to have been carried out by Al Qaeda (search). Arriving in Kuwait City for a meeting of the Gulf Cooperation Council, Prince Nayef (search) was asked whether Usama bin Laden's terrorist network was responsible.

"Yes, but we need time to confirm this," he said.

The first ABB employees -- all Europeans -- boarded a van for the Yanbu airport Monday night.

"Money is money, but it's not worth your life," said Armando Rosiglioni, 63, of Venice, Italy, who arrived in Yanbu 10 days ago on a three-month contract. "I don't want to take a stupid risk."

He said a charter flight would take the employees to the Red Sea port of Jiddah, 220 miles to the south, where they were to take commercial flights to their destinations on Tuesday.

A Western diplomat and an ABB official said all foreign ABB employees and their families would depart on chartered flights by Tuesday.

Journalists were barred from the meeting between Ambassador James C. Oberwetter (search) and Yanbu's American community. But Oberwetter later told a news conference that he had encouraged the families to leave the country.

"While we are doing this urging, the U.S. government is not in a position to cause that to happen," he said. "Those are individual decisions by private Americans and by those companies."

People who attended the meeting said the ambassador spoke bluntly. His message was, "It is time for us to pack our bags and go home. ... We cannot protect you here," said a teacher at a local American school. A colleague nodded in agreement.

Reflecting the tense climate in Yanbu, the two women -- like many foreigners -- refused to give their names.

"I'm very, very frightened," the teacher said. "We still don't know whether we are going to stay or not, but I think it's really time for us to leave."

She and her husband decided to stay after past bombings and attacks in Saudi Arabia, she said, but this time was different. Some teachers at the American school where she works saw the body of one of the victims being dragged down the street, she said.

The violence began Saturday when four men sprayed ABB's offices with gunfire, then tied the body of one victim to the bumper of a car and headed for the Ibn Hayyan Secondary Boys School. Shaken Saudi schoolchildren recounted how the attackers summoned them with gunfire to watch the body being dragged.

Two Americans, two Britons, an Australian and a Saudi died in the attack, which ended with gunbattles as police gave chase. All four attackers -- who police said were Saudi brothers -- were killed.

U.S. Embassy spokeswoman Lisa Swenarski said the body of one of the Americans was "badly mutilated," but she could not confirm the body had been dragged behind a car.

"We're still trying to determine what happened to him," she said.

ABB on Monday identified the dead as Americans Stephen LaGuardia, 62, and Philip Coplen, 53; Britons Michael Hardy, 44, and Michael McGillen, 52; and Australian Anthony Mason, 57. All worked for ABB except McGillen; he was a contractor.

The Saudi killed in the attack did not work for ABB and was not identified.

Terrorists have struck four foreign targets in Saudi Arabia in the past year. Oberwetter praised Saudi Arabia's pursuit of terrorists, and said the United States was working closely with its government.

Asked whether the departure of Americans amounted to a victory for the terrorists, Oberwetter said he didn't believe terrorism "is winning the game."

"I personally believe, because of the activities of the government of the kingdom and those who are charged with finding the bad guys ... the climate in general will be considerably improved," he said.

But some of the departing foreigners said that for now, there was too much violence to stay.

"My wife is crying and begging me to come home," said Dennis Guades, a 36-year-old Filipino engineer for ABB. "I need a job to support my family, but I don't want to die."