Seven civilian employees of a U.S. firm are now missing in Iraq, joining a growing number of foreigners from at least 12 countries to be snatched in recent days.

The U.S. military said seven employees of a Halliburton Co. (search) subsidiary and two American soldiers were missing after their convoy was ambushed Friday near Abu Ghraib, west of Baghdad.

Only one, Thomas Hamill (search), a 43-year-old truck driver from Macon, Miss., is known to have been abducted. His captors have threatened to kill and mutilate him unless U.S. troops ended their assault on the city of Fallujah. The deadline passed Sunday with no word on his fate.

"Our work is difficult and in a dangerous environment and we are angered and deeply saddened by this situation," Halliburton Co. said in a statement.

Halliburton declined to identify the six other missing workers or discuss details of the attack in order to protect their privacy, spokeswoman Wendy Hall said Monday. The company said the attacks happened during a routine mission for the U.S. Army Material Command.

Hall confirmed Tuesday that the seven employees were involved in a single ambush.

A State Department official speaking on condition of anonymity said Tuesday that four mutilated bodies have been found in Iraq. The remains had not been identified, and the official had no further information on the discovery.

Hall said Halliburton was aware that remains had been recovered in the country but added that there had been no identifications.

"While we are not yet certain of the identification of these brave individuals, and no matter who they are, we at Halliburton are saddened to learn of these deaths and are working with the authorities so the families can begin the grieving and healing process," Hall said.

Dan Senor, a coalition spokesman, said Tuesday that about 40 foreign hostages from 12 countries are being held by Iraqi insurgents, and that the coalition would not negotiate with "terrorists or kidnappers" to gain the hostages' release. He would not comment on efforts to free the captives.

More than 24,000 Kellogg, Brown & Root (search) employees and subcontractors are working in the Kuwait-Iraq region, Hall said. Their duties include extinguishing oil well fires and cleaning oil sites.

In Hamill's hometown of Macon, Miss., American flags went up on the main street as a gesture of support and Mayor Dorothy Baker Hines said the town would keep the lights on all night at some buildings as a reminder.

"It's the least we can do to be patriotic at a time like this and hope he'll be all right and get back home," said resident Kevin Mitchener, who was busy putting up American flags.

Sgt. Elmer C. Krause, 40, of Greensboro, N.C., and Pfc. Keith "Matt" Maupin, 20, of Batavia, Ohio, have been identified as the two missing soldiers.

Maupin was known in high school for his tenacity on the football field and in the classroom, friends and family said.

"We're pulling for him. He's a fighter," Dan Simmons, athletic director at Glen Este High School.

"Matt was a selfless kid on the football field," Simmons said. "He did whatever the coaches told him. He wasn't a starter, but he made the other kids play harder."

Halliburton, the firm that Vice President Dick Cheney (search) ran during the 1990s, offered workers $80,000 tax-free for working in Iraq for a year, or up to $120,000 with overtime. However, they are allowed to return home without questions.

Two men who drove trucks for Halliburton until this weekend, Stacy Clark and Stephen Heering, said it was becoming too dangerous in Iraq.

"You have to see it to believe it," Clark, 36, said after reuniting Monday with his wife in Houston.

Heering's truck was blown out from beneath him Thursday, forcing him to make a dangerous escape. He decided to return home.

The sentiment that drove Clark and Heering home is growing among truck drivers in Iraq, said Herring, 33.

"I'm done. I'll never go back," he said.