Nigerian police have arrested the masterminds behind the deadly Oct. 1 massacre at a state university in the northwestern town of Mubi that killed 46 students, many of whom were Christians, Christianity Today reports. Police also confirmed the gunmen were members of the Boko Haram Islamist sect, though Boko Haram denied involvement. Nigerian officials reported that the four university students who allegedly devised the attack acted in response to recent student government elections, targeting Muslims and Christians alike who were either newly elected student leaders or students who voted for them. However, persecution watchdogs and the Christian Association of Nigeria insist the gunmen specifically targeted Christians in the attack, only killing Muslims on accident. "CAN rejects the theory of election dispute as responsible for the massacre ... considering the way it was reportedly carried out," CAN national secretary Musa Asake said; according to several students who escaped the massacre, the gunmen first asked victims if they were Christians before shooting or knifing them.