ISIS has reportedly killed 25 people by lowering them into a vat of acid, as "an example" to others.
The group is alleged to have murdered 25 people in Mosul, all of whom were men, by lowering them into a vat of highly corrosive acid. The men had been accused of spying on behalf of the Iraqi government, and their execution was intended to be a public warning to others, according to the Daily Mail.
The vat the men were put into contained nitric acid, a liquid usually used to make ammonium nitrate, which is used in fertilizer and explosives. A witness said ISIS members tied each victim to a rope and lowered them into the tub of acid, leaving them there until their organs dissolved.
The executions come after a series of losses for ISIS, in which the group lost around 40 percent of the territory it had previously claimed in Iraq and 10 percent of the territory it had gained in Syria, though Pentagon spokesman Peter Cook said those numbers have gone up in recent weeks.
"The number right now in Iraq is about 45 percent of the territory they once held has been recovered," said Cook. "The number in Syria is anywhere between 16 to 20 percent."
The nitric acid executions are the latest in a series of killings by ISIS. In May 2016 it was reported the group killed a 7-year-old Syrian boy for insulting the caliphate, according to the Mirror. Muaz Hassan was reportedly playing with friends when a member of ISIS accused him of cursing.
"[ISIS] police arrested Muaz Hassan earlier this week in the city of Raqqa, after they heard him ‘cursing divinity,’ while playing in the street with his friends," said a source. "The act was considered an insult to the caliphate, regardless of the age of the boy."
The boy was put before an ISIS court where it was ruled that he should be executed for "insulting the caliphate." He was taken to a square where he was shot in front of 700 people.