CAIRO (AP) — The spokesman of Egypt’s military says 20 “terrorists” carried out a deadly border post attack that killed 22 soldiers, the deadliest assault on Egypt’s military in years.

A statement posted Tuesday on the official Facebook page of military spokesman Brig. Gen. Mohammed Samir said attackers driving four pickup trucks loaded with explosives first exchanged gunfire with soldiers at a border post in el-Wadi el-Gadid, Egypt’s largest province bordering Libya and Sudan.

The statement said the gunfire prevented the attackers from storming the post. However, it said attackers fired rocket-propelled grenades at a gas cylinder, blowing it up and causing a fire in an ammunition warehouse that exploded and killed the soldiers Saturday.

The statement did not say who the military suspects of carrying out the attack.

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