BAGHDAD (AP) — Authorities say an insurgent attack on a military barracks in northern Iraq has killed 20 troops.

Two police officers said Sunday that gunmen staged the assault late Saturday on the barracks in the village of Ayn al-Jahish outside the northern city of Mosul. They said some of the 20 Iraqi soldiers killed appeared to have been shot at close range.

A medical official, who confirmed the causality number, said 11 troops had their hands tied behind their backs and suffered close-range gunshots to the head.

All officials spoke on condition of anonymity as they were not authorized to release the information to journalists.

Mosul, a former insurgent stronghold, is located about 360 kilometers (225 miles) northwest of Baghdad.