A total of eight people were killed and 22 wounded in separate attacks in central and northern Iraq on Tuesday, the police said.

Two policemen were killed and two others wounded when a land mine detonated near their vehicle in the city of Sherqat, some 280 km north of Baghdad, a local police source told Xinhua on condition of anonymity.

In a separate incident, a policeman and 13 civilians were wounded when gunmen in their car hurled three hand grenades on a police checkpoint at a crowded marketplace in central the city of Mosul, some 400 km north of Baghdad, a source from the city police anonymously told Xinhua.

In Baghdad, gunmen using silenced weapons shot dead a government official in a drive-by shooting while he was driving his car in Jamia district in western the capital, an Interior Ministry source said on condition of anonymity because he was not authorized to speak to the media.

Earlier in the day, the police reported the killing of five people, including two policemen, and the wounding of six people in separate gunfire and bomb attacks in Iraq's western province of Anbar.

Violence has been increased in the Iraqi cities as the Iraqi security forces are preparing to take over control of security alone after the proposed departure of U.S. troops by the end of the year withdrawal deadline.