Islamic State militants in Nigeria have executed 11 Christian captives to coincide with Christmas celebrations, claiming the killings as revenge for ISIS leaders assassinated by U.S. forces this year.
The execution footage was released by ISIS' Amaq propaganda agency on December 26, according to the BBC. The 11 unidentified victims were all men and "captured in the past weeks" in Nigeria's northeastern Borno state, the terrorist group said.
The 56-second video was filmed at an unidentified outside location and shows militants lined up behind the 11 kneeling captives. The killings begin with the prisoner in the middle, who is shot dead before those alongside him are forced to the ground and beheaded.
ISIS said the executions were part of its effort to "avenge" leader Abu Bakr al-Baghdadi and spokesperson Abul-Hasan al-Muhajir, both killed within 24 hours of each other in Syria in October.
Baghdadi was killed during a special operations raid in the village of Barisha in the northwestern Syrian province of Idlib on October 27.
Hours later, Muhajir was killed in a U.S. airstrike near Jarablus in northwest Syria, close to the border with Turkey in territory controlled by Turkish-backed militants. President Donald Trump said Muhajir would have been Baghdadi's likely successor.
Baghdadi—the self-proclaimed ISIS caliph—led the group as it stormed across Iraq and Syria, establishing its so-called caliphate. Baghdadi also oversaw the expansion of the group via affiliate organizations across the globe which swore allegiance to him and his group.