KANO, Nigeria: Gunmen massacred at least 26 people in a student housing area of northeast Nigeria on Tuesday, calling victims out by name before shooting them or slitting their throats, officials said.
The attack occurred in the early hours in the town of Mubi, where the military last week carried out a high-profile raid against Islamist extremist group Boko Haram, which has been waging a deadly insurgency.
Some officials however suggested the massacre may have been linked to a recent student election.
According to a police spokesman, the attackers knew their victims and called them out by name in an off-campus area near a polytechnic school where students live.
The police spokesman, Mohammed Ibrahim, put the death toll at 25, including 19 students from the polytechnic, three students from a health technology school, two security guards and a retired soldier.
A relief official speaking on condition of anonymity said 26 people had been confirmed dead and 15 were wounded and taken to hospital. The military had taken over the area.
"The attackers knew their targets," Ibrahim told AFP.
"They were calling out names of their targets in each house they entered, and once the target identified himself, he would be shot dead. We strongly suspect an inside operation."
He added that some victims' throats were slit.
The suggestion that the killings were linked to the student election however raised questions over how and why the dispute would have turned so violent.
There were suggestions of ethnic tensions between the mainly Muslim Hausas and predominately Christian Igbos involved in the vote.
Violence has erupted between student gangs in the past in Nigeria, but it is not known to have previously led to a massacre on such a scale.
Nigerian officials have been seeking to show success in the fight against Boko Haram with a number of raids and arrests. There had been a lull in major attacks in recent weeks.
A spokesman for the National Emergency Management Agency said reports indicated some of the victims were candidates in the polls.
"The crisis in Mubi is suspected to have been fueled by campus politics after an election at the Federal Polytechnic," said the agency's Yushau Shuaib.
Abdulkarim Bello of the Red Cross said "they are conducting elections in the Federal Polytechnic and unknown gunmen just entered and sprayed people with bullets".
Nigeria's military said last week it had killed a senior Boko Haram leader and arrested 156 suspected members of the group during a raid in Mubi. The town had been placed under curfew during the raid, but it has since been lifted.
In September, Boko Haram claimed arson attacks on about two dozen telecommunication masts across northern Nigeria, with Mubi among the areas hit. Mobile phone reception has been badly affected in some areas.
Mubi is not far from the city of Maiduguri in neighbouring Borno state, which is considered the base of the Islamist group that is blamed for killing more than 1,400 people in northern and central Nigeria since 2010.
The town has seen previous such violence, including in January, when gunmen opened fire on Christian Igbos at a house as they mourned the death of a friend killed in a shooting the night before.
Residents and a relief official reported up to 17 people dead, while police said 12 were killed, with between two and five people killed the previous night in the same town.
Boko Haram has claimed to be seeking an Islamic state in Nigeria's mainly Muslim north, but its demands have repeatedly shifted and it is believed to include a number of factions with varying aims.
Nigeria's government has claimed to be engaging in back-channel talks in a bid to end the insurgency, but Boko Haram's suspected leader, Abubakar Shekau, denied dialogue had occurred, in a YouTube video posted on Sunday.
Nigeria, Africa's most populous nation and largest oil producer, is roughly divided between a mainly Muslim north and predominately Christian south.