BAGHDAD, July 8: Guerillas killed five US soldiers and two Iraqi guards in a mortar attack on National Guard headquarters in Samarra, north of Baghdad, on Thursday.

The attack came as a Lebanese-born US marine missing from his unit in Iraq, who was at one point reported to have been beheaded by his captors, was handed over to US officials in Beirut.

The latest attack came a day after Iraq's interim government announced a security law giving itself tougher powers to combat the guerillas. Eighteen US soldiers and four Iraqi guards were also wounded when guerillas fired mortar rounds at the National Guard headquarters, severely damaging the building, the US military said. The building is also used by US troops.

A US Army Apache attack helicopter fired Hellfire missiles at a nearby building after the strike, killing four guerillas, the US military said. American forces used radar to locate the source of the mortar fire and responded with 120-mm mortar rounds.

The deaths in Samarra, 100kms north of Baghdad, brought to 651 the US combat death toll in Iraq since the invasion in March last year. The National Guard, renamed by the interim government, is a 40,000-strong paramilitary force set up during the US-led occupation, when it was known as the Iraqi Civil Defence Corps. Outside Samarra, guerillas opened fire on a convoy of oil tanker trucks, killing two drivers, at least one of whom was Turkish, witnesses said.

HOSTAGE FREED: Uncertainty over the fate of US Marine Corporal Wassef Ali Hassoun, who went missing in Iraq on June 21, appeared to be resolved when US officials said he was at the American embassy in Beirut.