"One tank, in fact, did break down and we had to destroy it," deputy defense secretary Paul Wolfowitz told CBS television.

Another top Pentagon official said "the tank tread was knocked off by a rocket-propelled grenade so the tank itself could not move."

"The crew was not at all injured. They got out of the tank and joined their buddies in the rest of the column," General Peter Pace, vice chairman of the Joint Chiefs of Staff, told CNN.

Iraqi officials took journalists to see the wreck of a US Abrams tank on the outskirts of Baghdad, saying it was knocked out in intense fighting which killed five Americans on Saturday.

Iraqis with Kalashnikov rifles danced triumphantly over the damaged and charred tank in the Sayadia area, a southern entrance to the capital.

SPACE.WIRE