Three Isis fighters were reportedly killed by wild boars on Iraqi farmland controlled by the group.
The militants had been trying to remove the animals near Kirkuk in the al-Rashad region when the boars went on a “rampage”, Iraqi News reports.
One source claimed other Isis members “took revenge on the pigs” after the fatal attack occurred.
It was unclear exactly how the fighters died or how the “revenge” was carried out.
Isis have held areas surrounding Kirkuk since 2014, and several thousand civilians have reportedly fled from the region.
It comes six months after Iraqi forces launched efforts to retake the city of Mosul, thought to be the last stronghold of the group in the country.
However, there are fears that the offensive could push militants to regroup elsewhere. One fear is that the province of Kirkuk could become another stronghold.
Local forces in the region have repeatedly called on the government to liberate Isis-held areas, but its resources are predominantly occupied by Mosul.
Militants have been accused of executing civilians in the region who attempt to flee to refugee camps.