BAGHDAD, June 25 (Xinhua) -- An Iraqi police officer was killed and seven people injured in two bomb attacks and a mortar barrage in Baghdad on Thursday morning, a well-informed police source said.

    In early Thursday morning, a roadside bomb exploded near an Iraqi police foot-patrol in the predominantly Shiite neighborhood of Baladiyat in eastern Baghdad, killing a Lieutenant Colonel and wounding three policemen, the source told Xinhua on condition of anonymity.

    In a separate incident, two more policemen were wounded in a roadside bomb explosion near their vehicle in the al-Hurriyah Square in Karrada district in central Baghdad, the source said.

    Meanwhile, three mortar rounds landed on residential buildings on the Abu Nauwas Street, wounding two civilians, the source added.

    The mortar barrage apparently targeted the heavily fortified Green Zone which houses some Iraqi government offices and foreign embassies, including the U.S. one, he said.

    The barrage hit the buildings close to the zone, which were located just across the Tigris River that bisects the Iraqi capital. The Green Zone in central Baghdad, is frequently hit by rocket and mortar shells but seldom with casualties.

    The attacks came a day after one of the most deadly bomb explosions when a motor-cycle bomb struck a pet market in the Shiite slum of Sadr City in eastern Baghdad, killing 62 people and wounding more than 150, according to latest police reports.

    The attacks also came just a few days before U.S. combat troops are due to withdraw from Iraqi towns and cities, raising fear for a rebound of terror attacks at a time when Iraqi security forces finally struggle to stand on its own.

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