The bomb was detonated remotely when the victims' armored vehicle passed by during a security operation, the sources said, Reuters reported.
There was no immediate claim of responsibility, but a Takfiri insurgency in the Sinai has gained pace since the military toppled President Mohamed Mursi of the Muslim Brotherhood in 2013.
The militant group staging the insurgency pledged allegiance to Daesh (ISIL or ISIS) in 2014 and adopted the name Sinai Province. It is blamed for killing hundreds of Egyptian soldiers and police since then.