Major Austin Pearson, however, acknowledged he did not know if the explosives removed from the dump included HMX explosives or others declared missing by the International Atomic Energy Agency (IAEA).

The munitions have become a major topic of contention in the US election campaign, with Democratic White House contender John Kerry saying the loss of the explosive highlights mistakes made in Iraq by President George W. Bush.

The Pentagon had suggested the 380 tons of high explosives that the IAEA says vanished after the war was probably moved by Saddam Hussein's regime before US-led forces invaded Iraq in March 2003.

But the airing of film taken by a US television crew on April 18, 2003 at Al Qaqaa has stepped up pressure on the US administration.

The film shows US soldiers cutting what appeared to be IAEA seals on bunkers and finding crates and boxes filled with suspected high explosives.

Lawrence DiRita, the Pentagon spokesman, told a press conference that some units were assigned the task of removing explosives from the site.

He introduced Pearson, commander of an ordnance company, who said his unit moved about 250 tons of explosives, including plastic explosives, from Al Qaaqaa on April 13, 2003.

Pearson said the unit used nine trucks and trailers to removed ordnance from open bunkers at a location called "Objective Elms" within the sprawling complex to an ammunition holding site west of the Euphrates River called "Logistics Support Area Dogwood".

He said the munitions removed included TNT, plastic explosives and white phosphorous rounds as well as detonation cords and initiators.

He said he did not know what kind of plastic explosives were removed, or whether it included HMX, high melting point explosives.

Before the war, the IAEA had sealed bunkers containing HMX explosives because it could be used as a trigger in a nuclear device.

It said the Iraqi government reported this month that large amounts of HMX explosives, RDX explosives and a relatively small amount of PETN were missing from the facility, apparently looted after the US invasion.

DiRita said that while the explosives that Pearson's unit removed did not consitute all the missing explosives, "We believe it constitutes some portion of those weapons."

But Pearson said he did not see any IAEA seals at the locations.

"I was not looking for that. My mission specifically was to go in there and to prevent the exposure of US forces and to minimize that by taking out what was easily accessible and putting it back and bringing it into our captured ammunition holding area," he said.

He said he did not know if it was the same material that the IAEA has declared missing.

The videotape taken by a television news crew embedded with the 101st Airborne Division during the war showed US soldiers using bolt cutters to break into sealed bunkers at the complex.

The video showed barrels marked explosives and crates labelled Al-Qaqaa State Establishment.

"The photographs are consistent with what I know of Al-Qaqaa," David Kay, the former US chief weapons inspector in Iraq, told The New York Times.

"The damning thing is the seals. The Iraqis didn't use seals on anything. So I'm absolutely sure that's an IAEA seal," he said.

The Times quoted an unidentified weapons expert as saying said the video and some of the IAEA's photographs of the HMX stockpiles "were such good matches it looked like they were taken by the same camera on the same day."

DiRita was not prepared to say whether or not the barrels shown in the videotape were consistent with HMX.

In the face of attacks by Democratic presidential candidate Kerry, the Pentagon has strongly suggested the missing explosives were not looted but were moved before the war by Iraqis.

Defense Secretary Donald Rumsfeld said Thursday that "the idea it was suddenly looted and moved out, all of these tons of equipment, is I think at least debatable."

He added it was likely Saddam ordered the munitions moved when he knew the war could not be avoided.