The Islamic State (Isis) has executed 25 alleged spies by lowering them into a huge tub of nitric acid, until their 'organs dissolved', Iocal news source Iraqi News has claimed. The report could not be independently verified.

The alleged spies were captured in the IS (Daesh) stronghold of Mosul, in northern Iraq, accused of working for the Iraqi government's security forces.

Mosul is the largest city in Iraq still under IS control, but is facing increasing pressure from the north, south and east by the Iraqi army, Kurdish Peshmerga forces and US-led Western air strikes. A number of shocking and brutal killings have taken place at the hands of IS as they try to assert their domination over the the city, which Barack Obama had predicted would fall be the end of this year.

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According to witnesses of the killings, the 25 alleged 'spies' were tied together with a huge rope and lowered in a basin containing the highly corrosive acid. Nitric acid is generally used for manufacturing ammonium nitrate that can be used to make fertiliser and explosives but it can also be used for photoengraving, etching steel, and reprocessing spent nuclear fuel.

"ISIS terrorist members executed 25 persons in Mosul on charges of spying and collaborating with Iraqi security forces,' a source told Iraqi News in a statement. "ISIS members tied each person with a rope and lowered him in the tub, which contains nitric acid, till the victims organs dissolve."

On Wednesday (18 May), IBTimes UK reported the burning alive of a Christian child who asked her mum to forgive the Isis militants who torched her home. The courageous child, believed to be around 12-years-old, was burned in Mosul after her family were raided by the jihadists for 'Jaziya' — a religious tax.

Earlier this week, the US Defence Department estimated that Isis fighters lost control of about 40% of the territory they once had in Iraq and roughly 10% of the land they held in Syria. Army Gen. Joseph Votel, commander of U.S. Central Command, told reporters this week: "They are looking for ways to start to regain their momentum or regain the initiative".

Islamic State Mosul Iraq