Human Rights Watch on Friday accused Iraqi Kurdish security forces of carrying out mass executions of detainees alleged to be members of ISIS. The watchdog said the Kurdish peshmerga fighters detained Iraqis and foreigners at a school in Sahel al-Maliha, 70 kilometers northwest of second city Mosul, from which ISIS was expelled in July. "The evidence suggests that Asayish (Kurdish) security forces conducted mass executions of captured ISIS suspects night after night for a week, perhaps killing scores or even hundreds of male detainees," said Lama Fakih, HRWs deputy Middle East director. "Iraqi and KRG (Kurdish Regional Government) authorities should urgently and transparently investigate the allegations of mass executions and hold those responsible to account," she said in a statement, according to Agence France Presse. The executions allegedly occurred between August 28 and September 3. Questioned about the report by HRW, Iraqi Kurd government official Dindar Zebari denied the accusations. Zebari said that according to the head of the Asayish, the peshmerga were battling ISIS on a 71-kilometer front line as the militants attempted to flee to Syria. During the clashes, many ISIS and peshmerga fighters died, and "the corpses of the killed ISIS members in this fighting were probably brought in one place to be buried", he was quoted as saying. The front line is located about 40 kilometers from the site at which the bodies were found, said HRW, casting doubt on his account. "This explanation does not match the state the bodies were found in, shot in the head" and buried "in a solitary desert area, far from where any fighting had occurred," said the watchdog. “Because the mass grave site is located within the flood zone of the Mosul Dam reservoir, it is critically important to urgently allow international forensic experts to conduct a detailed exhumation of the site before seasonal rains fill the reservoir again later this year,” Reuters cited the HRW report. The Peshmerga in July assisted a US-backed offensive by Iraqi forces to capture Mosul, the de facto capital of the so-called ISIS “caliphate” declared in 2014 over parts of Iraq and Syria. Iraq declared victory over ISIS in December but the group has morphed into an underground organization and continues to claim attacks across Iraq.