As a special forces officer in the Egyptian Army, Hisham al-Ashmawy trained in the desert, learning camouflage, survival techniques and how to hunt the enemy in rough terrain. Now he has turned militant and uses that training to help fellow jihadis fight the government.

Ashmawy's background makes him a potent figure among Islamist fighters, who President Abdel-Fattah el-Sissi say pose an existential threat to Egypt. "Ashmawy is the most dangerous terrorist we face," an Egyptian National Security official said. "He is the mastermind and executor."

Security officials say the former military man, whose allegiance has switched from the Islamic State group to al-Qaida, has carried out some of the most high-profile attacks in Egypt. These include the attempted assassination of former Interior Minister Mohammed Ibrahim in May 2013, and the killing in June this year of Egypt's top public prosecutor in a car bomb.