According to AFP, Boko Haram's leader said a northeast town seized by the insurgents earlier this month has been placed under an Islamic caliphate, in a video obtained by AFP on Sunday (August 24).
"Thanks be to Allah who gave victory to our brethren in (the town of) Gwoza and made it part of the Islamic caliphate," Abubakar Shekau said in the 52-minute video.
In a July video, Shekau voiced support for the leader of the Islamic State (IS) militants Abu Bakr al-Baghdadi, who in late June 2014 declared himself "the caliph" and "leader of Muslims everywhere."
COMMENT: It seems apparent that having seen the media responses to the brutality of IS militants, Boko Haram seemingly is attempting to emulate the mistreatment of prisoners it captures.
Yet, there was no confirmation Shekau in the latest video that he was associating himself with Baghdadi, whose Sunni Muslim fighters have taken over parts of Iraq and Syria.
There was no confirmation that Shekau was actually in Gwoza for the filming; his whereabouts remain unknown but another unidentified fighter who speaks later in the video vowed that Boko Haram would retain control of northeastern Nigeria.
The UN humanitarian office (OCHA) earlier this month confirmed reports that Gwoza was under Boko Haram control.
Boko Haram is also believed to be in control of other areas near Gwoza in southern Borno, as well as large swathes of territory in northern Borno and at least one town in neighboring Yobe state.
Experts have described Boko Haram's gains in recent weeks as unprecedented, saying the terror group was closer than ever to achieving its goal of carving out strict Sharia Law across northern Nigeria.
A lack of commensurate weapons for troops sent to combat Boko Haram has hampered the counter-insurgency and some soldiers this week refused to deploy to Gwoza without better equipment in an apparent mutiny.
After Shekau's 25-minute speech, the video reveals militant fighters on pick-up trucks firing rocket-propelled grenades and other heavily armed insurgents firing weapons as they walk nonchalantly along a rural road.
The end of the video apparently depicts scenes of grisly executions, similar to those released by IS in recent weeks.
In one scene, about twenty Nigerian men in civilian clothing are shown with their hands tied behind their backs and lying by the roadside before they are shot at close range.
A second image depicts two men, whom Shekau said disguised themselves as women to escape the area, are beaten beaten to death with shovels. Two others similarly dressed are shot beside what appears to be a trench full of recently killed civilians.