At least seven US troops have been killed in roadside explosions and attacks in Iraq, officials have said.

Four were killed and their Iraqi interpreter injured when a roadside bomb exploded next to their vehicle north-west of the capital Baghdad.

Two soldiers were killed and three wounded when their vehicle was hit by a bomb and shot at in Baghdad.

An airman also died of his wounds in a roadside blast near his vehicle in Saddam Hussein's hometown of Tikrit.

In another incident, a US soldier based in Baghdad died from what was described as a non-combat related cause, reports said.

The deaths brought the toll of US military personnel killed in Iraq since March 2003 to more than 3,500.

PHOTO CAPTION

US soldiers on patrol in Dora