Meanwhile, a previously unknown Islamist group claims to have captured two US soldiers in Iraq, Lebanon's LBCI satellite television reported Friday, showing what it said were photocopies of the pair's military identity cards.

The group, calling itself Fukat al-Madina al-Munawara, or Medina Faction, after the Muslim holy city in Saudi Arabia, named the two as Katherine V Rose and Andrew Peters, and said that they had been taken in a clash in which two US soldiers were also wounded, LBCI reported.

Th US Army however denied the claim.

Spokesman Specialist Anthony Reinoso only confirmed that one soldier died after being caught in a fire at 4:30pm (1230 GMT) Thursday that broke out in a building on a shooting range in Baghdad's Karrada district.

He died 20 minutes later from smoke inhalation, Reinoso said, adding that six others were wounded.

It was not clear if the fire was accidental or a case of arson, he said. Earlier, a spokesperson had called the death "a fatality," but gave no further details.

In the second incident, a soldier with the Marine Expeditionary Force was killed near Hilla, 100 kilometers (60 miles) south of Baghdad, said Sergeant Amy Abbott.

The soldier was shot Thursday by an unidentified man who approached the sports utility vehicle he was being driven in as it was slowed by congested traffic, a statement from US Central Command said.

"According to initial reports, a male approached the vehicle, shot the service member, and ran into a crowded market area nearby," the statement said.

He was taken to the Forward Resuscitation Surgical System at Camp Babylon, where he was pronounced dead.

The Hilla killing brought to 64 the number of US soldiers killed in guerrilla attacks in Iraq since Washington declared major combat over on May 1.