Colonel Ismail al-Juburi, commander of the anti-terror squad in the town of Al-Sharqat, was travelling to the provincial capital Tikrit when a magnetic "sticky bomb" attached to his car detonated, killing him and wounding his driver, a police lieutenant colonel and a doctor at Tikrit's main hospital said.

The attack came a day after violence in northern Iraq killed three people -- a female judicial investigator, a police sergeant and an anti-Qaeda militiaman.

Violence in Iraq is down dramatically from its peaks from 2006 to 2008, but attacks remain common -- 278 people were killed in August, according to an AFP tally based on reports from security and medical officials.