At least 45 Islamic State fighters died after eating a fast-breaking Ramadan meal in the Iraqi city of Mosul Tuesday, Haaretz reported.

According to Saeed Mamozeny, a spokesman for the Kurdish Democratic Party, 145 ISIS fighters took part in the iftar meal, the traditional evening meal when Muslims end their daily Ramadan fast at sunset.  Shortly afterwards, 45 members were reported dead.  The spokesman also said that they have not determined if the cause was food poisoning or deliberate poisoning.

Mosul, once with a population of over 1 million, was captured last June by Islamic State fighters. It is the largest city in the group’s self-declared caliphate,.

ISIS has reportedly suffered casualties as a result of poisoned food in the past. In November, the Times of Iraq reported that Free Syrian army militants had infiltrated an ISIS camp, posed as cooks and poisoned their lunches. Dozens of ISIS fighters subsequently died.

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