Baghdad:  A suicide car bomber detonated his explosives-packed vehicle at a prison north of Baghdad on Monday, killing 11 people and wounding at least 15, security officials said.

The bomber blew up the car at about 8:00 am local time at the main entrance of the Hout prison in Taji, about 25 kilometres north of Baghdad, officials from the interior and defence ministries said.

The casualties include policemen, security forces guarding the prison, and prison employees, the officials said.

The interior ministry official said 11 people were killed and 20 wounded, while the defence ministry official put the toll at 11 dead and 15 wounded.

Both spoke on condition of anonymity.

It was not immediately clear if the attack was part of a prison escape attempt, which are fairly common in Iraq.

Violence has declined nationwide since its peak in 2006 and 2007, but attacks remain common. A total of 258 people were killed in October, according to official figures.

General Lloyd Austin, the top US commander in Iraq, has warned that the country's security situation is likely to see "turbulence" as American forces depart and groups including Al-Qaeda seek to take advantage of the vacuum.

American troops are set to leave Iraq by the end of 2011.

(Agencies)