At least 21 people were killed on Sunday in an attack on church premises in eastern Democratic Republic of Congo by a rebel group, according to a civil society leader.

The attack was carried out by members of the Allied Democratic Force (ADF) around 1 am inside the premises of a Catholic church in eastern DR Congo's Komanda. Several houses and shops were also burnt.

"More than 21 people were shot dead inside and outside and we have recorded at least three charred bodies and several houses burned. But the search is continuing," Dieudonne Duranthabo, a civil society coordinator in Komnada, told The Associated Press.

A spokesperson for the Congolese army in Ituri province, where Komanda is located, confirmed 10 dead.