– ISIL propagandists released a video Tuesday showing the group’s fighters incinerating, drowning and blowing up men accused of helping the U.S. and U.S. allies bomb its bases.

The video was one of ISIL’s most gruesome and appeared to suggest internal concern that civilians living in areas under the group’s control could be working against it.

The propagandists included a personal message intended for a lieutenant in the Iraqi police force, Lt. Bassem Mohammed, who has been struggling to obtain salaries and arms for a group of former policemen wanting to fight ISIL in Ninevah Province. Mosul, Ninevah’s provincial capital, is the largest city controlled by ISIL.

Mohammed said that he knew about half of the 16 prisoners seen being killed in the video and that he was related to many of them. “It was my father, my cousin, my uncle and others,” he said.