Security agents have begun a manhunt for the gunmen who invaded Mubi, Adamawa State, on Monday night, killing about 46 students from three higher institutions in the state.
Their search for the killers Wednesday led to a house-to-house search in Mubi during which an unspecified number of suspects were arrested.
The state Police Commissioner, Mohammed Ibrahim, who confirmed the arrest to Reuters, declined to give further details.
The search began just as President Goodluck Jonathan ordered the security forces to intensify efforts to fish out the killers, widely believed to be Boko Haram insurgents, while Senate President David Mark called for capital punishment for the attackers.
The gunmen who had attacked students of the Federal Polytechnic, Adamawa State University and the School of Health Technology, all in Mubi, were said to have gone from room to room in a building in the town on Monday and killed the people they found there with guns and machetes.
However, the police were also said to be investigating whether the killings were as a result of a feud inside the college.
Ibrahim said the police were still keeping an open mind on whether the killing spree was carried out by militants or rival students, but there were signs of an "inside job".
"Relatives of the slain students said the assailants called their names out before killing them. The majority were killed with gun shots or slaughtered like goats," he added.
One possibility was that the killings were related to a dispute between rival groups at the Federal Polytechnic, Mubi, following a student union election on Sunday, Ibrahim said.
"The second day after the election winners were declared, you have the killings ... Really we cannot rule out the possibility that the attack may have been carried out by either the Boko Haram or a ... gang," he added.
Jonathan, who was briefed about the incident, along with other cabinet members, by the Minister of Education, Prof. Ruqayyatu Ahmed Rufa'i, at a meeting of the Federal Executive Council (FEC) Wednesday in Abuja, condemned the attack.
According to the Special Adviser on Media and Publicity to the president, Dr. Reuben Abati, Jonathan described the killings as tragic, sad, barbaric and shocking.
"The president has directed security agencies to investigate the matter and get to the root because this kind of incident, where people are called out and shot, is really shocking," he said in a statement.
Mark, while reacting to the attack, advocated capital punishment for the killers to serve as a deterrent to others.
Mark, in his remarks while the Senate was considering a motion by Senator Bindowo Jibrilla, from Adamawa North Senatorial District, said the time has come for the country to test the capital punishment clause as enshrined in the statute books.
Before observing a one-minute silence for the victims of the attack, the Senate urged the Federal Government to swiftly bring the perpetrators to book.
Mark added that the need to provide security in the area had become expedient because of the swelling insecurity in the region.
He said: "The security challenges before us in this country are grievous and we have to tackle them headlong. On the specific issue of this are the Mubi killings.
"I think it is a pity that people will go from one room to the other calling names and slaughtering the people. It is totally unacceptable. Even if it is just attacking the symptoms now, those involved must be arrested and brought to book.
"I know that this is a democracy and with due respect to all of us, but capital punishment is still in our statutes."
He said the time and opportunity had come for the country to apply the death clause in the statute books and use it as a deterrent to others.
While blaming government for its slow response to security emergencies, he said: "It is not that crimes don't take place in other places; they do. But it is the reaction of government; the speed with which those involved in crimes in other countries are arrested, tried and punished accordingly that differs.
"However, when they happen in this country, after a week, we tend to forget it and wait for the next one to happen.
"I think we have gone beyond the point of singing these songs of lamentations over and over again. We should not be lamenting, we should be able to act. And government needs to act as swiftly as possible."
Mark urged both the Federal Government and states to live up to their responsibilities of providing security to the citizenry.
"I think this is a very serious issue and if we don't tackle the real issues and begin to go on diversionary expeditions, we will be missing the point.
"Terrorists will succeed once they can stop you from doing what you want to do and once they can stop government from doing what they want to do, they want all Nigerians to be very scared of sending their children to polytechnics and universities. I think there are very serious challenges and we must address them," he added.
In her contribution, Senator Oluremi Tinubu, representing Lagos Central Senatorial District, attributed the insecurity facing the country to lack of good governance and leadership failure.
She said: "The expectations of the people are that government should provide power and security for the citizenry. The attack in Mubi is evidently a sign of a failed state."
In his contribution, Senator Barnabas Gemade said the killings, especially in some Northern parts of the country, could have been orchestrated to disrupt the economies of the area. He suggested that security around the borders and the cities in this region be strengthened.
The National Coordinator of Human Rights Writers' Association of Nigeria (HURIWA), Emmanuel Onwubiko, also condemned the massacre in Mubi.
Speaking at an event to mark the fifth anniversary of HURIWA, Onwubiko said: "This bestial, cruel, crude and inhuman action of the armed attackers was reprehensible, despicable and absolutely condemnable."
According to him, the presidency's reaction to the massacre was unfortunate, sad, disappointing and shocking.
He accused the Federal Government and the state governments in the North of failing to restore and institutionalise the rule of law and respect for the sanctity of life as provided in Section 33(1) of the 1999 Constitution.
Also speaking at the event, the National Chairman of the All Progressives Grand Alliance (APGA), Chief Victor Umeh, called for the inclusion of the right to good governance as a constitutional provision in the ongoing amendment to the constitution.
He said this would enable Nigerians to use the courts to remove from office any leader that errs.