MOSUL, Iraq, July 7 (Xinhua) -- Four policemen and a gunman were killed in two attacks in the city of Mosul, the capital of Nineveh province, on Tuesday, a well-informed provincial police source said.

    A gunman opened fire from his assault rifle on a police patrol in the Rasheriyah neighborhood in northern Mosul, killing two policemen, the source told Xinhua on condition of anonymity.

    Policemen in the patrol fired back and killed the attacker, the source said.

    In a separate attack, armed men attacked a police checkpoint in Muthanna neighborhood in northern Mosul, killing two more policemen before they fled the scene, the source added.

    Mosul, some 400 km north of Baghdad, has been a stronghold for insurgent groups, including al-Qaida organization.

    The attacks came a few days after the pullout of U.S. troops from Iraqi towns and cities, according to an agreement signed late last year between Baghdad and Washington.

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