The Egyptian military has said they have killed 29 suspected militants and arrested dozens in the restive northern Sinai region during surprise raids.

An army spokesperson said the raids took place between 20 and 30 April in the Sinai Peninsula.

Brigadier General Mohamed Samir said the raids were carried out in Rafah, Al-Arish and Sheikh Zawayed cities. He added that 133 militants were arrested and 51 insurgent hideouts destroyed.

"Twenty-nine terrorists were killed in shootouts with army and police troops in northern Sinai between April 20 and 30," the army spokesperson said in a Facebook post.

Samir said the detained militants had participated in "terrorist plots" against Egyptian security forces.

Seven bombs which were planted by Islamist militants were also detonated under controlled conditions and dozens of vehicles and motorbikes were also destroyed.

The Sinai Peninsula, located on the region bordering Israel and the Gaza Strip, has been reeling under fighting for several months after the military launched an offensive against the insurgents.

Ever since former dictator Hosni Mubarak was toppled in 2011, the militants have been stepping up their attacks targeting the police and the army.