The US military said Sunday an operation targeting gunmen from the Al Qaeda terrorist network in the northern Iraqi city of Mosul left four people dead, including a woman and a child.

In the operation Saturday, Al Qaeda suspects riding in a vehicle refused to stop, after coalition troops fired warning shots, prompting the forces to engage them, a military statement said.

The woman and the child, who were also in the vehicle, were killed in the engagement along with two gunmen.

A US military spokesman, Capt. Gordon Delcambre, said the forces 'sincerely regret when innocent civilians are killed' during anti-Al Qaeda operations.

Iraqi security forces Saturday launched an offensive against the terrorist network in Mosul, which has become the centre stage of operations for Sunni insurgents regrouping there after they were driven out of Baghdad in recent months.

In another statement Sunday, the military said a US soldier died Saturday when a vehicle he was riding in rolled over in Asad, home to Iraq's second largest air base.

The death in Asad, 180 km west of Baghdad, brings the number of US soldiers killed in Iraq since March 2003 to 4,075.