Islamic State militants killed up to 770 captured Iraqi soldiers after they captured a former US military base in Tikrit back in June, a new report by Human Rights Watch (HRW) said on Wednesday.
Three new mass execution sites have been discovered at the Camp Speicher air base near the Iraqi city of Tikrit, the international human rights group HRW stated in its report, bringing the total number of sites to five.
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According to HRW, the massacres were carried out by militants of the Islamic State (formerly known as ISIS or ISIL) following the siege of the city, located about 190 kilometers north of Baghdad.
The report states that the hardline Islamist group killed anywhere between 560 and 770 men during the slaughter, most of them believed to be Iraqi security forces serving at the former US base.