BAGHDAD, Sept. 15 (Xinhuanet) -- The police chief of western Iraqi town of Khaldiya was killed by unknown gunmen on Monday, witnesses said.

　　The officer, known as Colonel Khudayer Mukhlif, was killed in his car Monday afternoon on the road from Fallujah to Khaldiya, the witnesses said.

　　Three of his colleagues were also wounded when a group of masked fighters opened fire at their car from a passing-by pick-up, they added.

　　The incident took place three days after nine Iraqi policemen were killed by US troops in what the US military said a "friendly fire" incident on Friday in Fallujah, 50km west of Baghdad.The US military issued a statement of apology on Saturday, but failed to give a clear account, which prompted angry tribesmen to vow to revenge.

　　One US soldier was killed and another wounded Sunday morning at the entrance to Fallujah when their convoy hit a roadside bomb. Another US soldier died on Monday in the capital city of Baghdad after he suffered a fatal wound in a rocket-propelled grenade attack.

　　Resentment against the US occupation and cooperation with the US-led coalition forces came the strongest in the area west and north of Baghdad. Enditem