Iraqi police officials say a massive truck bomb has ripped through a popular Baghdad food market in the early morning hours, killing at least 54 people.

The two police officials say the truck detonated in the Jameela market in Baghdad's crowded Sadr City neighborhood shortly after dawn on Thursday. They say at least 86 people were wounded in the attack.

Three hospital officials confirmed the casualty figures. All officials spoke on condition of anonymity as they're not authorized to speak to the media.

No one immediately claimed responsibility for the explosion, but Islamic State militants commonly target predominantly Shiite neighborhoods such as Sadr City, with the goal of sending a message to the Shiite-dominated government.

The Sunni militant group currently holds territory in about a third of Iraq.