Two U.S. Marines were killed in Iraq when their vehicle was hit by a roadside bomb, the military said on Tuesday, pushing the total U.S. military death toll since the 2003 invasion to 1,999.

A military statement said the Marines died on Friday near the town of Amariya outside Falluja, a focus of the Sunni Arab insurgency against the U.S.-backed Baghdad government.

The statement said the deaths were in addition to two other military personnel, a Marine and a sailor, who were earlier reported killed in the incident.

U.S. military casualties are now just one short of the headline-grabbing 2,000 figure -- which is expected to spur fresh calls for U.S. President George W. Bush to outline an exit strategy for the conflict in Iraq.

One U.S. soldier, Sergeant Keith Maupin, is listed as missing following his capture in an attack on a supply convoy in April last year. He was shown with armed men in video released by a militant group shortly afterward. His whereabouts are unknown, but a later insurgent video said he had been killed.

Reliable figures for the number of Iraqis killed since the March 2003 U.S.-led invasion are not available but non-governmental organizations estimate at least 25,000 have died.

Copyright © 2005 Reuters Limited.

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