Iraqi officials say a suicide car bomber has struck a military convoy north of Baghdad, killing five soldiers.

Police officials say the bombing took place on Tuesday when the bomber rammed his explosive-laden car into a convoy of army vehicles in Tikrit. The city is located about 130 kilometers (80 miles) north of Baghdad.

The officials say the explosion also wounded 11 soldiers.

Medics confirmed the casualty figures. All officials spoke on condition of anonymity because they were not authorized to talk to the media.

Violence has escalated in Iraq over the past year.

According to United Nations figures, Iraq last year saw the highest death toll since the worst of the country's sectarian bloodletting began to subside in 2007.