Egypt has declared a three-month state of emergency in parts of the Sinai Peninsula after some of the worst anti-state violence since President Mohamed Mursi was overthrown last year.
On Friday, 33 security personnel were killed in two attacks.
The first, a car bomb in the al-Kharouba area northwest of al-Arish near the border with the Gaza strip, killed 30 people including several senior army officers. More than 25 people were wounded.
Hours later, gunmen opened fire on a checkpoint in al-Arish killing three people.
Security forces have been battling militants who have killed hundreds of soldiers and police since the army toppled Mursi last July.
President al-Sisi has expressed concern over militants thriving in the chaos of post-Gaddafi Libya. They are opposed to the Cairo government.
Officials are also worried that IS fighters appear to have forged ties with radical groups in Egypt.