Eight insurgents have been killed and at least four United States Marines wounded during fierce fighting in the Iraqi city of Fallujah, where an uneasy ceasefire had been in place for a week, the US -led coalition said."
A "significant" number of insurgents reportedly attacked Marines, prompting hours of fighting in the northern district of the city.
" Initial reports were eight enemy killed and four Marines wounded ," Colonel John Coleman, chief of staff for the 1st Marine Expeditionary Force, told reporters.
Marines were fired upon from a mosque which was then targeted by US forces and the minaret destroyed, an embedded pool reporter with the marines told CNN.
He said another six Marines were injured by shrapnel but the reports could not be immediately confirmed.
" Unfortunately the opposition forces ? took it upon themselves to occupy a mosque ," Mr Coleman said.
" Instead of serving as a centre of religious life, it was employed as a bastion in the attack ."
He said Marines used small arms and a tank machine gun against the insurgents in the mosque during the battle in the northern district of Jolan.
US Marines and Iraqi guerrillas have exchanged heavy fire in two districts of the besieged town of Fallujah, local residents say."
Clashes in the Golan and Shuhada districts broke out around 11:20am local time and are continuing.
Insurgents are firing rocket-propelled grenades, while the troops use heavy machineguns mounted on vehicles.
US troops who were at a chemical storehouse that exploded in Baghdad on Monday appear to have included members of the Iraq Survey Group (ISG) hunting for weapons of mass destruction.
Residents have shown a Reuters reporter at the scene identity cards belonging to members of the ISG.
The residents say they found the cards after US soldiers evacuated their casualties.
The reason for the blast is not immediately clear but witnesses say it happened when about 12 US soldiers tried to break into the building.
The structure was destroyed in the explosion and at least one unidentified body and four wounded Iraqis have been evacuated.
A powerful explosion in Baghdad's northern neighbourhood of Waziriyah has blown up two US Humvees and caused a nearby house to collapse.
Reporters at the scene say two Humvees can be seen burning as US forces close off the area.
An Abrams tank and a Bradley armoured vehicle are also at the scene as fire trucks rush to the area, where several chemical plants are located.
Residents say they saw rocket propelled grenades being fired into the Humvees as they passed by.
A powerful bomb has exploded in Baghdad's northern neighbourhood of Waziriya, destroying four US military vehicles."
No occupation forces spokesman was prepared to comment on casualties after the Monday morning attack, but as many as 12 marines may be dead.
An Iraqi policeman, who refused to give his name, said he saw "three US soldiers wounded or killed in each vehicle".
Heavy black smoke could be seen rising above a chemical storehouse that appears to have been booby-trapped.
One witness, Imad Hashim, said the bomb went off " when they [US marines] tried to force their way in, there was a huge ball of fire and I was thrown to the ground ".
Hashim said he was about 100 metres away from the blast.
Four Humvees were seen burning as US forces closed off the area, residents said they also saw rocket propelled grenades being fired into the Humvees as they passed by.