Twenty-six Egyptian soldiers were killed or wounded on Friday in attacks on several checkpoints in Sinai that included car bombings, the military said in a statement.
The military said it killed 40 assailants as it clashed with extremists in North Sinai, where the Islamic State group is leading a deadly insurgency.
The sources said two vehicles were detonated while passing a checkpoint in an area between Rafah and Sheikh Zuweid. No group has claimed responsibility for the attack.

Egypt faces an Islamist insurgency led by Islamic State in North Sinai, where hundreds of soldiers and police have been killed since 2013, when the military ousted Islamist president Mohamed Mursi after mass protests.