GETTY ISIS are conducting chemical weapons experiments on humans

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The extremist group has reportedly poisoned prisoners using spiked food and water with compounds used in pesticides. Security forces now fear the group may be hatching a twisted plot to contaminate Western food supplies with easily dissolvable substances. Records of the sick experiments had been stashed away at Mosul University, and were only found after Iraqi special forces recaptured the city from ISIS fighters.

The paperwork revealed that one victim was fed thallium sulphate - a colourless, tasteless salt - causing him to suffer a fever, nausea and swelling of the brain and stomach, before dying in agony ten days later. Thallium sulphate is available for sale in many countries, including the US, and is commonly used as a rat poison. Described by ISIS as “an ideal lethal poison”, the documents suggest the terror group may be in “possession of an ample amount of the solution to fill demands”.

Chilling photographs from inside Mosul Wed, June 21, 2017 Iraqi forces battle to retake the last enclaves held by Islamic State militants Play slideshow REUTERS 1 of 12 An Iraqi special forces soldier checks men for explosive belts as they cross from Islamic State controlled part of Mosul to Iraqi forces controlled part of Mosul

In another experiment, the group injected a nicotine-based compound - said to have no antidote - into a separate victim who passed out within seconds and died hours later. Ingredients for this poison are usually contained in cigarettes and vaping supplies, and are also widely available. The chemical weapons report also contained recipes and guides for producing the toxic nicotine compound. The documents describing the human experiments were verified by British and US forces, and were later obtained by The Times.

GETTY Iraqi Counter-Terrorism Services advance in West Mosul's Al-Najjar neighbourhood

Chemical weapons expert Hamish de Bretton-Gordon told The Times: "This is a horrifying throwback to the Nazis who would test nerve agents on live humans. “During the Second World War, the Nazis conducted thousands of deadly experiments with mustard gas on prisoners at Sachsenhausen concentration camp, near Berlin.” ISIS has recently lost territory in Mosul and now controls just one-tenth of the city following a surge by Iraqi forces in October.

GETTY Displaced Iraqi women queue for water and food aid in west Mosul

The group has allegedly used Mosul University - one of the largest educational institutions in the Middle East - to develop chemical weapons over the last three years. The university was recaptured in January, forcing the group to move their headquarters to Raqqa, in Syria. Reports have also suggesting the terror group has now recruited weapons experts from around the world.