Army Apache helicopters attacked number of suspected sites used by armed groups in North Sinai on Sunday, killing and injuring 25, a military source said.
Egypt Independent earlier reported that army helicopters were combing North Sinai to root out suspected militants involved in the killing of 16 soldiers last August and the abduction of seven security troops in February.
The military source added that the number of militants killed in South Sheikh Zuwayed had risen to eight.
Fifteen people had earlier been reported killed and seven others injured.
Abu Ziad, a local eyewitness, said the Apaches combed the area before targeting villages late Saturday.
Armed militants responded with anti-aircraft missiles.
The attacks left local villages severely damaged. In some, security forces told residents to stay at home for their own safety while aircraft carried out bombings.
A security source said that the military operation had been a great success, with successful hits on terrorist sites.
Military forces are monitoring other locations for targeting later, the source added.
Five civilians and a police recruit were meanwhile injured in a series of militant attacks on police stations and checkpoints.
Egyptian authorities also decided to re-open the Rafah crossing with the Hamas-controlled Palestinian Gaza Strip for four hours, following a four-day closure for the Eid holiday.
