The U.S. military says coalition forces have killed 10 insurgents in a shootout at a safe house northwest of Baghdad.

A U.S. statement says troops approached the house early Tuesday while its occupants, including a guard, were sleeping. The statement said rifles, ammunition and explosives were recovered at the scene.

In Baghdad, a bomb hidden in a minibus near a market in the Iraqi capital exploded Tuesday, killing two people and wounding at least five others.

Police say bomb hidden inside minibus exploded in central Baghdad's Shorja district, killing at least two people, wounding five

Separately, U.S. authorities say a roadside bomb blast in northern Baghdad wounded two American security contractors and killed a nearby ambulance crewman.  A similar bombing killed a U.S. soldier late Monday south of Baghdad.

Meanwhile, the U.S. military says an Iraqi court convicted 12 insurgents in April for crimes, including membership in a terrorist organization.  Three defendants received life sentences.

In another development, a U.S. expert has released a report saying engineers leading U.S.-led reconstruction efforts in Iraq have made substantial progress, despite setbacks caused by security problems.

But the Pentagon report also criticizes a U.S. task force set up to help Iraqis protect their oil and gas facilities. It says the task force has failed to meet its goal of boosting Iraqi oil production back to pre-war levels.

The study also says a U.S.-funded contractor that promised to build 150 health care clinics in Iraq has only completed six, and has already spent three-quarters of its budget.