Nigerian soldiers moved house to house on Wednesday in an urgent bid to hunt down attackers responsible for the massacre of 26 people who were shot or had their throats slit in a student housing area.
The attack in the early hours of Tuesday near a polytechnic university shook the town of Mubi, located in Nigeria's volatile northeast.
"The military is going house to house searching," said Abubakar Ahmed, head of the Red Cross in Adamawa state, where Mubi is located.
Motives for the gruesome attack remained unclear. In Mubi last week, the military carried out a high-profile raid against Islamist extremist group Boko Haram, which has been waging a deadly insurgency.
But some officials 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 a student housing area off-campus of Federal Polytechnic Mubi. Victims were shot or had their throats slit, he said.
The town had already been under a 3:00 pm to 6:00 am curfew in the wake of last week's raid, and it remained in place on Wednesday.
The suggestion that the killings were linked to the student election 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.
At the same time, Boko Haram has continually widened its targets and its attacks have become increasingly sophisticated.
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.
The Islamist extremists have been blamed for more than 1,400 deaths since 2010 as part of their insurgency in northern and central Nigeria, Africa's most populous nation and largest oil producer roughly divided between a mainly Muslim north and predominately Christian south.