On Thursday an Egyptian security forces camp in Ismailiya, near the Sinai Peninsula, was targeted by a massive explosion, leaving at least 35 policemen injured. Officials told Al Jazeera the bombing was followed by gunshots.
Egypt has seen massive protests and general unrest since President Mohammed Morsi of the Muslim Brotherhood was deposed on July 3. The military has cracked down on the Muslim Brotherhood since, arresting top leaders of the movement.
In particular, the military has been active in the Sinai, conducting operations to stem the wave of attacks in the region.
Earlier on Thursday, hundreds of Muslim Brotherhood supporters protested near the Ministry of Defense headquarters in Cairo. Police responded by firing tear gas and water cannons to disperse the demonstrators.
Since Morsi's deposal, over 1,000 people have been killed, most of them Muslim Brotherhood supporters. The military has arrested roughly 2,000 Islamists over that time period.