Forty bodies have been found in a mass grave in Ramadi, a provincial capital west of Baghdad recently taken back from Islamic State.

The grave in central Ramadi contained the bodies of police and civilians, including women and children, interior ministry spokesman Brigadier General Saad Maan said.

Video footage from the site shows local security forces and a small forensics team wearing face masks and digging with shovels.

Ramadi, the provincial capital of the sprawling Anbar province, fell to IS in May, marking a major setback for US-backed Iraqi forces.

Iraqi troops retook the city centre last month with heavy coalition air support.

Mass graves have been found in other areas liberated from the IS group, which has publicised its massacres of Shiites and other opponents.