CAIRO (Reuters) - Three policemen, one security guard and a civilian were killed and a number of other people injured in an attack by militants in Egypt’s North Sinai province on Monday, the interior ministry said.

The militants attacked a security post securing a National Bank of Egypt branch in Arish, the provincial capital, with explosives and guns, a statement said.

Egypt is fighting an insurgency against militants affiliated with Islamic State in the northern part of the Sinai Peninsula where hundreds of security forces have been killed since 2013.

Attacks on security forces have been common since Islamist president Mohamed Mursi was ousted in 2013 following mass protests against his rule.

The militants raided the bank branch and stole an amount that had yet to be valued, the statement said. Forces were searching the area for the perpetrators and had defused some explosives.

Security sources told Reuters that three Egyptian policemen, one security guard and three civilians were killed and 22 others were injured in the attack.

Witnesses said armed militants in five cars fired on security forces near a church and the NBE branch before fleeing the scene.

“The militants fired shots randomly in the street as if they were celebrating, with some of them raising their black flags (of Islamic State). They roamed the streets for about 20 minutes then disappeared,” said Alaa Lotfy, a shop owner in the area who witnessed the clashes.

At least 24 militants and six soldiers were killed on Sunday in attacks on military outposts in North Sinai.