At least eight members of Egypt's security forces have been killed in an attack on a checkpoint in the northern Sinai.
There was no immediate claim of responsibility for the attack.
A military spokesman said in a statement the military killed three of the assailants.
An Islamist insurgency in the rugged, thinly populated Sinai Peninsula has gained pace since the military toppled President Mohamed Mursi of the Muslim Brotherhood, Egypt's oldest Islamist movement, in mid-2013 following mass protests against his rule.
There have been conflicting reports on what happened.
The statement said that a car bomb and an explosive device lead to the death of eight military personal.
However, other security sources said earlier that assailants fired two rocket propelled grenades at the checkpoint south of the city of al-Arish, and three pick-up trucks carrying masked men then drove by and opened fire.
The militant group staging the insurgency in Sinai pledged allegiance to Islamic State in 2014 and adopted the name Sinai Province. It is blamed for the killing of hundreds of Egyptian soldiers and policemen since then.
In its weekly online magazine Al-Nabaa released on Thursday, Islamic State urged members to join other branches of the group active in areas like the Sinai, Libya, Yemen and West Africa if unable to reach its self-declared "caliphate" in Iraq and Syria.
Islamic State had previously called on members to carry out attacks in their home countries if unable to enter Iraq or Syria because of tougher security measures in the region aimed at cutting off jihadist supply lines.