Five aid workers abducted last month in Nigeria Borno State have been killed.
The men were working for Action Against Hunger, the International Rescue Committee, Rich International and the country’s State Emergency Management Agency, Nigeria’s president confirmed.
Muhammadu Buhari vowed to bring the killers to justice.
He also pledged to “wipe out the remaining vestiges” of the Islamist group, which has dominated the region.
The group’s decade-long insurgency has left thousands dead, displaced many more and resulted in a humanitarian crisis. Aid workers have frequently been targeted, especially by a Boko Haram splinter group affiliated to the so-called Islamic State group.
The Nigerian online newspaper Premium Times says the killers belong to a sect of Boko Haram and posted a 35-second video of the executions.
According to the newspaper, the hostages were held by five hooded armed men.
An unidentified voice delivers a speech to “the infidels” telling them to “repeat and turn to God” before one of the gunmen orders the others to shoot their captives.