EXPLAINER: Who are the gunmen abducting Nigerian students?

LAGOS, Nigeria (AP) — The recent release of three separate groups of students who had been abducted in northern Nigeria brought joyful reunions and the hope that others still held might soon be freed. Now just days later gunmen have again attacked a school in the northwest, taking 73 new hostages. Before Wednesday’s attack some 1,000 students had been kidnapped in about a dozen school abductions since December and UNICEF says some 200 are believed to still be in captivity. Government officials describe the gunmen carrying out the attacks as “bandits” but what, if any, connection there is between them remains unclear. School kidnappings have taken place in nine of Nigeria’s states, and targets have included everyone from preschoolers to university students.