Six Egyptian policemen were killed on Tuesday when an explosion struck an armoured vehicle in North Sinai, the interior ministry said.
An IED planted on the Rafah-Arish road caused the blast as the vehicle passed by.
Security sources told Reuters' Aswat Masriya that the IED device was planted in a small tunnel dug by the assailants under the sidewalk on the Rafah-Arish road.
A police officer and five conscripts were killed, while two others were injured.
Police and military sites and personnel have been a target for militant jihadists in North Sinai as authorities continue to fight an Islamist insurgency in the tumultuous peninsula.
Earlier in September, 11 security personnel were killed and four others injured, also in an IED attack, in Sheikh Zuweid city.
Meanwhile, the army has targeted militant hideouts with helicopters and ground troops, killing scores in recent months.
Military spokesman Brigadier-General Mohamed Samir said on Monday that army forces had killed 10 "terrorists" and arrested 17 others between 13 to 14 September in ambushes on their hideouts.