The remains of 85 ISIS fighters and their relatives have been exhumed from a mass grave in the northern Iraqi city of Mosul.
In 2014, ISIS had seized large parts of Iraq and Syria, killing thousands of people after declaring a caliphate in those areas.
Iraqi authorities said they had found the remains of 35 people killed between 2016 and 2017 on Saturday and 50 others on Sunday.
"Work is ongoing," said Hassan Wathiq Al Anzi, the head of forensics in Nineveh province, northern Iraq.
Workers unearthed bones and skulls, placing them in black bags for transportation to the forensic department, an AFP report said.
It is the first announcement of a mass grave of ISIS fighters killed during the 2016-2017 battle to recapture Mosul, the extremist group's former stronghold.
Mr Al Anzi was unable to provide either an estimate of the total number of bodies at the site or the precise circumstances of their deaths.
Iraq declared victory over ISIS in late 2017 after reclaiming the northern and the western regions seized by the extremist group in 2014.
But remnants of the group have been carrying out a low-level insurgency, particularly in the north, that is disrupting efforts to restore stability to Iraq after years of warfare and sectarian unrest.
The UN said the group left behind more than 200 mass graves that could contain as many as 12,000 bodies.
The burial site was behind a mosque in a residential area in the Al Rifai district and DNA samples will be taken to identify the bodies, Mr Al Anzi said.
Nineveh's civil defence said that while digging began on Saturday, the authorities had previously been aware of the site's location.
Iraq continues to discover mass graves not only from the ISIS period but also from the regime of former dictator Saddam Hussein, who was toppled in a US-led invasion in 2003.