Police in Iraq say a car bomb has exploded at a Shi`ite mosque in Baghdad, killing at least five people and wounding at least 20 others.
Authorities say the explosion occurred during midday prayers Friday, at the al-Subeih mosque.
Also Friday, the U.S. military said an American soldier was killed by a roadside bomb north of Tall Afar, a city about 150 kilometers east of the Syrian border.
On Thursday, the Iraqi militant group Islamic Army in Iraq claimed responsibility for shooting down a civilian helicopter north of Baghdad and killing the six American contractors, three Bulgarian crew members and two Fijian guards on board.
The group posted video footage on the Internet of what is says was the wreckage of the helicopter. It also showed a purported survivor of the crash being shot on the ground after asking for help.