File photo provided by the Nigerian military shows weapons captured during operations againstBoko Haram terrorists in Nigeria's northeastern state of Borno, Nigeria, Feb. 24, 2016. (Xinhua)

ABUJA, July 29 (Xinhua) -- The death toll of weekend attacks by Boko Haram in Nigeria's northeastern state of Borno has so far risen to 70, according to local sources on Monday.

More bodies were recovered by rescue workers between Sunday and Monday morning in Nganzai local government area of Borno where three villages were attacked by Boko Haram militants on Saturday, one rescue official, who led the operations in the area, told Xinhua by telephone.

The official, who preferred to be anonymous, said at least 15 bodies were recovered since Sunday evening. Most of the bodies were found in the bush, having bullet wounds.

Babagana Umara Zulum, the governor of Borno, told Xinhua earlier on Sunday that 55 bodies of villagers were found after the militants' three separate attacks in Badu Malam Kyariri, Zawa and Lamisula Bukar Bulala villages.

Another rescue official said the recovered bodies were being prepared for mass burial on Monday.

Abbagana Ali, head of the Civilian Joint Task Force, a pro-government militia group in the area, said Sunday dozens of the victims were killed while conducting a funeral at a local cemetery.

Ali told Xinhua that a funeral was being held at a graveyard in Badu Malam Kyariri village when the Boko Haram militants struck on Saturday morning.

The militants stormed the village in five gun trucks mounted with anti-aircraft guns, he said.

Muhammad Bulama, head of the Nganzai local government area, suspected that the Boko Haram militants' onslaught was a reprisal attack.

According to Bulama, two weeks ago, an attack on the village by the Boko Haram militants was repelled by a joint force of troops and the village's vigilante group.

At least 11 Boko Haram fighters were killed in that attack two weeks ago, the official added.

Boko Haram, which launched attacks in Nigeria's northeast a decade ago, is known for its agenda to maintain a virtual caliphate in the most populous African country.