Umbrella group representing cattle herders says explosion was caused by Nigerian military jet but officials say blast in north central Nasarawa state was caused by a drone, without specifying who was operating it.
The death toll from a bomb blast that struck a group of herders in central Nigeria has risen to 40 from 27, the local government said.
The explosion on Wednesday took place in Rukubi, a village on the border between Nasarawa and Benue states, a region known for ethnic and religious violence.
"We now have approximately 40 people that were killed," Nasarawa's Governor Abdullahi Sule told reporters on Thursday.
"The rumour earlier was that the air force carried out the bombing, but right now we understand that there was no air force plane that flew (above) the area," Sule said on Arise News TV late Wednesday.
"Instead, it was a drone that flew (above) the area and dropped the bomb," Sule said, without specifying who was operating the aircraft.
An umbrella group representing herders had said the explosion was caused by a Nigerian military jet.
"We all know it is only the military that possesses jets to carry out aerial strikes," Lawal Dano of the Miyetti Allah Cattle Breeders Association of Nigeria said on Wednesday, calling for a government investigation.
READ MORE: Bomb kills 27 herders in central Nigeria: police
There have been accidental air strikes on civilians by the military in the past in northern Nigeria, where troops are fighting militants and criminal gangs.
In September 2021, officials said an accidental Nigerian military air strike on a village in Yobe state killed at least nine civilians.
The air force said its jet had been pursuing a group of militants in the area.
In January 2017, at least 112 people were killed when a jet struck a camp housing people displaced by militant violence in the town of Rann, near the border with Cameroon.
The Nigerian military blamed a "lack of appropriate marking of the area" for that bombardment in a report issued six months later.
In central Nigeria, herders and farmers have been clashing over grazing and water rights for decades, but the violence has worsened in recent years after some herders joined criminal gangs that raid villages.
The conflict has also taken on an ethnic and religious dimension, with most herders being Muslims while farmers are largely Christians.
Last Thursday, nine people were killed when suspected herders opened fire outside a camp for people displaced by attacks near Makurdi, the capital of Benue state, according to local officials.
Security is a major issue in Nigeria ahead of next month's elections to replace President Muhammadu Buhari, a former army general.
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