Armed men have killed the chief of police in a town northeast of Baghdad, Iraqi security officials said.

Colonel Hatim Rashid Muhammad was killed along with an aide during an ambush in Balad Ruz, 50km northeast of the capital.

Balad Ruz lies in the mixed Sunni and Shia Muslim province of Diyala, where fighters frequently attack US-backed security forces.

Fighters have been increasingly attacking the Iraqi police and military, who have taken a larger role in trying to stabilise the country in recent months, supported by about 160,000 foreign troops.

Car bombers mounted two attacks on Iraqi soldiers in northern Iraq on Thursday, killing at least seven people.

Targeted killings

There has been a series of targeted assassinations of police chiefs and senior Iraqi military commanders in recent weeks.

Last month, the police chief in a southern Baghdad district was gunned down on his way to work.

And the commander of the Iraqi National Guard in the southern city of Basra was assassinated along with his son while visiting Baghdad.

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