Medics and residents say armed "bandits" attacked five villages in northwest Sokoto state, killing more than 70 people, but there was no immediate official comment on killings.
Armed criminals on motorcycles killed dozens of people in a string of attacks on villages in the restive northwest of Nigeria, medics and residents said.
Dozens of gunmen — described locally as "bandits" —raided five villages close to the border with Niger in Sokoto state late Wednesday, sources told AFP news agency.
Lawal Kakale, a local traditional leader in Sabon Birni district, said the death toll had risen to 74 from an earlier figure of 60 as more bodies were recovered in the villages.
"We recovered 25 corpses in Garki, 13 in Dan Aduwa, 25 in Kuzari, seven in Katuma and four in Masawa," he told AFP.
"People fled in all directions and were pursued by the attackers. So, the corpses were scattered."
'Bodies had bullet wounds'
Medics at the nearby hospital said they initially received 60 corpses with gunshot wounds in the wake of the assaults.
"All the bodies had bullet wounds, most of them were shot in the head," a medic said on condition of anonymity.
There was no immediate official comment from police but security sources said there would be a press conference later Thursday.
Regional governor Aminu Waziri Tambuwal said the attack came as a "rude shock" as security officials had recently visited the area to try to calm tensions.
Years of violence
Northwestern Nigeria has been wracked by years of violence involving clashes between rival communities over land, attacks by heavily armed criminal gangs and reprisal killings by vigilante groups.
Cattle rustling and kidnapping for ransom have flourished in the security vacuum.
Sabon Birni district, 175 km from the state capital Sokoto, has in recent times been repeatedly attacked by armed gangs.
On Monday 18 people were killed when gunmen raided five other villages in Sabon Birni district, local officials said.
Nigeria's armed forces last week launched bombing raids against camps in neighbouring areas of the northwest as part of the latest efforts to curb attacks.
The army said the bombing campaign had killed hundreds of "bandits" but there has been no independent confirmation of the death tolls.
Authorities have previously launched repeated military operations and local peace talks to try to end the violence.
But so far neither strategy has succeeded in halting unrest that has killed an estimated 8,000 people since 2011 and displaced 200,000.
Fighters in Sahel
The International Crisis Group warned last week that militant groups waging a decade-long insurgency in northeast Nigeria are gaining influence in the northwest of the country.
The Brussels-based researchers said the region risked becoming a "land bridge" to fighters across the Sahel.
The group said there needed to be closer cooperation between the security forces in Nigeria and Niger to stop the flow of arms across their porous border.
Local leaders in Sokoto have said residents increasingly look to soldiers from Niger for protection and accuse the Nigerian army of failing to respond to attacks.