A force of 1,000 US soldiers launched Operation 'Iron Fist' in and around the village of Sadah in the restive Euphrates Valley on Saturday, the latest offensive aimed at rooting out al-Qaeda-linked insurgents in the border region.

"Coalition Forces, including helicopters from 2nd Marine Aircraft Wing, engaged and killed eight armed terrorists in fighting early in the day Oct. 1," according to a US military statement.

In one engagement, a combat helicopter destroyed a vehicle after its driver fired on a marine position with a rocket-propelled grenade. The rebel was killed.

The offensive is "intended to deny al-Qaeda in Iraq terrorists the ability to operate freely in the Euphrates River Valley and to prevent the terrorists from influencing the local population through murder and intimidation," the military said.

In mid-September, US and Iraqi forces mounted a large-scale operation to recapture the town of Tal Afar, in northwestern Iraq, which had fallen under the sway of insurgents.

The United States has long accused Syria of not doing enough to stop foreign fighters crossing into Iraq.

In Baghdad, one civilian was killed and one wounded Sunday when four mortar shells fell around the Iraqi interior ministry, a ministry official said.