Egyptian security officials say seven civilians and three militants have been killed in an exchange of fire between militants and the army in North Sinai.

The officials, speaking on the condition of anonymity because they were not authorized to speak to reporters, say a mortar round killed seven civilians from a prominent Bedouin family in the village of Negah Shabana.

Over the past decade, the northern region of the Sinai Peninsula has become a hub for Islamic extremists, and the insurgency has spiked since last year's military ouster of Islamist President Mohammed Morsi.

The military has launched a massive crackdown against militants in the area, including demolishing hundreds of homes along the border with the Gaza strip.