At least 50 members of a western Iraqi tribe in Anbar province were killed by Islamic State militants on Friday, according to officials and tribal leaders. The attacks are thought to be in retaliation for the Al Bu Nimr tribe’s resistance to ISIS. An official from Anbar province told the Associated Press that tribesmen and women were lined up and shot by militants in the village of Ras al-Maa. Earlier on Friday, mass graves containing between 80 and 220 bodies, many from the same tribe, were found. The graves are said to contain victim’s of ISIS’s attack on the town of Hit, from which many of the executed 50 had been displaced.