The commander of the Army Reserve unit that failed to report for a planned fuel convoy in Iraq has been relieved of that duty at her own request, the Army announced Thursday.

In a terse statement, the Army said the outgoing commander of the 343rd Quartermaster Company was "not suspected of misconduct" and that the move "has nothing to do with the guilt or innocence of anyone involved."

She will be reassigned commensurate with her rank and experience, the statement said, noting that the Army was withholding her name to protect her privacy.

The incident occurred last Wednesday, when 18 soldiers from the company failed to report for a the convoy from Tallil Air Base across central Iraq to Taji, a base north of Baghdad.

According to statements from relatives who have spoken with some of the soldiers, they were concerned about the roadworthiness of their trucks, the lack of a helicopter escort and, according to one account, the possibility that some of the helicopter fuel they were transporting was contaminated.

The Army has called the episode a "temporary breakdown in discipline" that it is investigating, but has ordered the unit to undergo a two-week "safety maintenance stand-down" during which operations will be suspended while inspections are conducted.

In London, meanwhile, Britain's Defense Secretary Geoff Hoon announced to the House of Commons that about 850 British troops and support personnel will move to more dangerous patrol areas closer to Baghdad in response to a U.S. request.

The move is intensely controversial in Britain, even among members of Prime Minister Tony Blair's ruling Labor Party. "The government has decided that we should accept the U.S. request for assistance," Hoon told parliament. "A UK armored battlegroup consisting of the 1st Battalion the Black Watch and supporting units will deploy . . . to relieve a U.S. unit for other tasks."

"This deployment is a vital part of the process of creating the right conditions for the Iraqi elections to take place in January," Hoon said.

While not detailing the exact mission or destination of the troops, Hoon said they would remain under British command.

U.S. military officials requested the movement to free up U.S. forces battling insurgents in flashpoints such as Fallujah.

Britain, America's strongest ally in the war, has roughly 8500 troops in Iraq, most of them stationed in the south, away from the worst violence of the Sunni triangle in the north.

In other developments Thursday, gunmen fired on a bus carrying Baghdad airport employees to work, killing four people and wounding 11, wire services reported.

One attacker threw at least two hand grenades into the packed bus and then three gunmen opened fire on the vehicle from outside, strafing it with bullets , according to the Reuters news agency.

Also Thursday, the husband of Margaret Hassan, the head of CARE International in Iraq who was kidnapped Tuesday, pleaded for her release at a press conference in Baghdad.

Tahseen Ali Hassan, addressing the kidpappers, asked them to "release my wife. She's Iraqi; she's working for a humanitarian organization and I ask you to release her."

Margaret Hassan was abducted on her way to work early Tuesday by gunmen who blocked her route and dragged the driver and a companion from the car, her husband said, according to wire service reports.

Hassan's kidnapping was probably the highest profile abduction of the roughly 130 carried out in the country.