The overnight strikes against "a terrorist group" responsible for killing police and army troops in north Sinai left "25 people dead and injured", army spokesman Colonel Ahmed Aly said.
He said a weapons and ammunition depot "which was being used for terrorist acts against the armed forces and police, terrorising the innocent citizens of North Sinai" was also destroyed.
A military source said 15 people were killed in the attack that saw Egyptian military helicopters target militants near the village of Touma, close to Sheikh Zuwayed.
Militants based mainly in north Sinai near Israel's border have escalated attacks on security forces and other targets since July 3, when the army ousted Islamist president Mohamed Morsi and installed a new government in Cairo.
The Egyptian army has been engaged in a campaign to curtail the surge in violence and rein in militant activity in the lawless Sinai.
An Egyptian militant group, Ansar Beit al-Maqdis, said four of its members belonging to Sinai Bedouin tribes were killed by Israeli drones on Friday. Egypt, which has a 1979 peace treaty with Israel, denied the report.
