Four US soldiers killed by explosion in Iraq

Baghdad: Four US soldiers were killed and four other soldiers injured by an explosion during combat operations south of Baghdad on Saturday, the US military said on Sunday.

The four deaths bring the number of US troops killed in Iraq to at least 3,688, since the 2003 US-led invasion to topple Saddam Hussein.

The US military said the soldiers were part of Task Force Marne, which has deployed in areas south of Baghdad to stop the flow of weapons, explosives and Shiite and Sunni Arab militants into the capital.

About 30,000 extra troops have been sent to Iraq since February as part of a security crackdown designed to buy time for Baghdad's fractured coalition government to meet a series of political targets set by Washington.

The targets are meant to promote reconciliation between Iraq's warring Shiite majority and minority Sunni Arabs, who were dominant under Saddam.