Updated

A former soldier from western New York is among the four Americans and one Austrian who were kidnapped in southern Iraq last week, family members said Sunday.

Jonathon Cote, 23, a native of Getzville, N.Y., a suburb of Buffalo, was working as a guard for Crescent Security Group when he was captured Thursday, his stepmother said. Family members spoke to The Associated Press on condition of anonymity out of fear for Cote's safety.

"The waiting is very tiring, and stressful," his stepmother said. "Your mind goes from very optimistic, good thoughts to thoughts that maybe something good is not going to happen."

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Before working for Crescent, Cote spent four years in the Army and served in Iraq and Afghanistan. He was stationed at Fort Bragg with the 82nd Airborne Division before receiving an honorable discharge, and has been in Iraq since June.

The five contract employees went missing when a truck convoy being escorted by Crescent was ambushed near Safwan, a largely Sunni Arab city of 200,000 people on the Kuwait border. Suspected militiamen dressed in Iraqi police uniforms seized 19 of the convoy's trucks, the five security guards and nine foreign drivers who were later released.

Another of the contractors is Paul Reuben, 39, a former police officer in the Minneapolis suburb of St. Louis Park, Minn., who is described by friends and family as an "easygoing, fun-loving type of guy" who was ready to come home.

His twin brother, Patrick Reuben, told the Star Tribune that Paul Reuben had been in Iraq for about two years working for Crescent and intended to come home after earning enough money to buy a house and a Hummer.

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Suzanne Reuben said that her most recent contact with her brother was a few weeks ago, when they exchanged instant messages by computer. He told her he hope to be home by the day after Thanksgiving.

Islamic Companies, a previously unknown group, claimed responsibility for the kidnapping, according to an Iranian-run Arabic-language satellite news station, which said the group demanded the withdrawal of U.S. forces from Iraq and the release of all prisoners being held there.

U.S. Embassy spokesman Michael McClellan said on Sunday that U.S. officials believe the five hostages are still being held captive.