The 22-year-old student has been named as Ropvil Daciya Dalep, who came from the Pankshin Local Government Area of the Plateau state and attended the University of Maiduguri in Borno state.
His execution was shown in a video released by the Islamic State-affiliated Amaq News Agency.
In the footage, a masked child speaks to the camera and says that Dalep’s killing is revenge for the “bloodshed” committed by Christians, according to Christian Solidarity Worldwide.
“In particular, this is one among the Christians from Plateau State,” the child is reported to have said in the video.
“We are saying to Christians, we have not forgotten what you have done to our parents and ancestors and we are telling all Christians around the world, we have not forgotten and will not stop.
“We must avenge the bloodshed that has been done like this one.”
Dalep was abducted on January 9 as he was returning to university to continue his studies in biology following the Christmas break.
His death has been blamed on the Islamic State West Africa Province, a Boko Haram splinter group.
Christian Solidarity Worldwide said that Dalep shot in the head by the masked child.
His death coincides with the execution of Rev. Lawan Andimi, the chairman of the Christian Association of Nigeria in Adamawa State by Boko Haram.
CSW’s Chief Executive Mervyn Thomas said that the Nigerian government needed to be “more proactive” in addressing Nigeria’s security issues.
“CSW is deeply concerned and saddened by the daily reports of violence against Christians in northern and central Nigeria, who are under siege from a multiplicity of armed non-state actors,” he said.
He added: “The continuing deterioration in security clearly highlights the urgent need for a recalibration of military strategy to ensure that security forces are sufficiently resourced to combat every armed threat and to protect every citizen, regardless of creed or ethnicity.”