WARNING: Graphic images below.



ISIS militants take aim at captured Iraqi soldiers in Tikrit. (Photos by Welayat Salahuddin via Associated Press)

On Sunday, militants from the Islamic State of Iraq and Syria (ISIS) posted a set of gruesome images online that purported to show them executing dozens of men, apparently from the Iraqi army, in Salahuddin province, north of Baghdad.

As my colleagues Liz Sly and Abby Hauslohner reported, some of the photos showed men in civilian clothes lying with their face down, shoulder to shoulder and with their hands bound, in a ditch surrounded by yellow fields, as a row of masked fighters fired into the ditch. Photographs taken before the execution show the men said to be Iraqi soldiers lining up before they are piled onto pickup trucks and then led to an open field. A report in the New York Times says the group boasted on Twitter that it had killed as many as 1,700 soldiers, which, if true, would make Sunday's execution one of the worst atrocities in the region in the past few years.

According to the Associated Press, the images were posted on the jihadist Web site Welayat Salahuddin by ISIS and their authenticity was confirmed by Iraq's top military spokesman, Lt. Gen. Qassim al-Moussawi, who said he was aware of cases of mass murder of Iraqi soldiers.

See the images below:



ISIS fighters lead away captured Iraqi soldiers.



ISIS militants watch over captured Iraqi soldiers, who appear to be piled onto the back of a truck.



ISIS fighters stand next to dozens of captured Iraqi security forces members.



ISIS fighters capture Iraqi soldiers after taking over a base in Tikrit.



ISIS fighters lead captured Iraqi soldiers to an open field.



Captured soldiers are lined up at an unknown location in Salahuddin province.



An ISIS fighter appears to execute captured Iraqi troops in Salahuddin province.



An ISIS fighter, holding a flag of the organization, fires at captured Iraqi soldiers.

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