Human Rights Watch confirmed Friday that 160 to 190 men were killed in mass executions by ISIS earlier this month in Iraq. ISIS posted pictures of the executions online, and HRW confirms today that they happened in at least two separate locations in Tikrit between June 11th and June 14th.

ISIS originally claimed online it executed 1,700 Iraqi soldiers. HRW has so far been able to confirm 160 - 190 deaths by analyzing the photos and satellite imagery, but emergencies director Peter Bouckaert said the death toll could be higher. He called for a full investigation into the executions, warning, "[ISIS] and other abusive forces should know that the eyes of Iraqis and the world are watching."

Here's one of the photos that ISIS originally published:

The U.N. reported this week that at least 1,075 people — many of them civilians — have been killed in Iraq this month. ISIS now controls most of Iraq's western border, and the militants have promised to take Baghdad.

Meanwhile, on Friday Iraq's top cleric, Grand Ayatollah Ali al-Sistani, officially called for Prime Minister Nouri al-Maliki to step down. He told worshippers during a sermon in the holy city of Karbala that political leaders must agree on a new prime minister, parliament speaker, and president by Tuesday. On Tuesday, parliament will meet to discuss a political solution to the crisis.

[Image via AP]