Military spokesperson Mohamed Samir revealed in a statement on Tuesday the details of primary investigations into the killing of 22 Egyptian border guards in a deadly attack last Saturday, reported the Ahram Arabic news website.
According to Samir, the attack was conducted by 20 armed men in four vehicles loaded with highly explosive devices. The armed men used sniper guns, machine guns, RBGs as well as hand grenades.
The militants tried to storm into the military checkpoint but failed. However, one of the RBGs set fire to gas cylinders in the checkpoint setting the installation and its ammunition storage ablaze causing the highest number of casualties.
When backup came to the rescue the militants escaped leaving some of their weapons behind and the body of one of the militants killed.
The deadly attack took place on Saturday in Al-Wadi Al-Gedid governorate, 630 km west of Cairo.
Their funeral of the slain soldiers was held Sunday at Almaza military airport in Cairo, where the bodies of the 22 borders guards have been resting since arriving Saturday night.
Saturday's attack is the biggest single act of violence against army or police since last August when 25 police conscripts were killed near the North Sinai city of Rafah.
The Egyptian presidency announced Saturday three days of national mourning.