Air raids in northern Sinai have killed 19 members of Egypt's ISIL affiliate, including three of its leaders, according to the Egyptian military.

There was no immediate comment from the Islamic State of Iraq and the Levant (ISIL) group in response to the Egyptian army's claim.

The military said in a statement on its official Facebook page on Thursday that the raids were directed at Ansar Beit al-Maqdis, a Sinai-based group that has been blamed for the killing of hundreds of Egyptian soldiers and police.

The group pledged allegiance to ISIL, also known as ISIS, in 2014 and adopted the name Sinai Province.

The military did not name the leaders it had killed in the air raids, but described one as among the group's most prominent members, and another as the head of its Islamic law committee. The third was an official in charge of interrogations, the army said.

ISIL this week claimed an attack on security forces near St Catherine's Monastery in the south Sinai, the latest incident in a spate of violence targeting Egypt's Christian minority in recent months.

Egypt has for years been battling an armed movement in the rugged and thinly populated Sinai Peninsula which has gained pace since the military overthrew democratically elected president Mohamed Morsi of the Muslim Brotherhood in mid-2013.