The families of civilians killed in October when an aircraft apparently mistakenly struck a place of worship in northern Iraq said on Monday they were suing top officials.

The relatives of the victims of the October 21 air strike in the town of Daquq told reporters they were filing suit against Prime Minister Haider al-Abadi, the defence ministry and the head of the air force.

"Several families and lawyers of the victims of the Khani husseiniyah (a Shiite place of worship) affected by the aerial bombing are filing class action," Haider Ahmed al-Daquqi, one of the relatives, told AFP.

Abadi is commander-in-chief of the armed forces and Anwar Hama Amin is the head of Iraq's air force. The post of defence minister is currently vacant.

The preliminary findings of a government investigation into the strike, that killed 14 people and wounded more than 100, suggest the strike was carried out by an Iraqi aircraft.

Most of the victims were women and children, gathered in a section of the husseiniyah that is reserved for them.

Daquq lies south of Kirkuk and about 200 kilometres (120 miles) north of Baghdad. There was no jihadist activity there at the time of the strike, and the area is mostly under Kurdish control.