An explosive device went off in North Sinai's al-Arish town on Thursday, targeting a security patrol and injuring 18 policemen, reported the state news agency MENA.
Those injured included 4 conscripts, a security source told MENA.
Militancy has surged in North Sinai since the 2013 military ouster of Islamist president Mohamed Mursi, following mass protests against his rule.
Militants escalated their attacks last week, when the Sinai-based militant group Ansar Bayt al-Maqdis conducted a string of simultaneous attacks on a number of checkpoints and a police station, in a failed attempt to take over the town of Sheikh Zuweid.
The attacks claimed the lives of 17 army personnel and injured 13, according to military figures.
The armed forces has responded with intensifying its crackdown on the peninsula, killing nearly 250 suspected militants in the past week, as per military figures.
