Egypt’s military chief on Wednesday called on his compatriots to hold mass demonstrations to voice their support for the army and police to deal with potential “violence and terrorism,” a move that signals a stepped-up campaign against backers of the ousted Islamist president.

Gen. Abdel Fatah al-Sissi, addressing a military graduation ceremony, said a massive turnout would give him a “mandate” and an “order” to do what is “necessary” to stop bloodshed.

A Muslim Brotherhood-led alliance of factions opposed to the military’s July 3 coup against Mohamed Morsi said Sissi’s call was an “open invitation” to civil war and urged Egyptians to boycott the pro-military rally. The alliance plans marches of its own Friday, raising the specter of violence.

Sissi’s address in the coastal city of Alexandria was a strong sign that the top general is the source of real power in Egypt, despite his assertions that authority has been handed over completely to the civilian government set up after Morsi’s fall.

The military’s removal of Morsi followed four days of protests by millions of Egyptians. Since then, Morsi’s Islamist supporters have taken to the streets vowing to continue protests until he is restored to power. Clashes have erupted multiple times between the Islamists and Morsi opponents or security forces, and dozens have been killed, mostly from the pro-Morsi side.

Throughout, the military and its allied news media have depicted the protesters as a dangerous armed movement. The Muslim Brotherhood and its allies say their protests are peaceful. The group accuses troops or “thugs” hired by the Interior Ministry, which is in charge of the police, of attacking pro-Morsi rallies.

At the same time, Islamist militants have stepped up attacks on security forces in the Sinai Peninsula since Morsi’s fall, killing nearly 20 soldiers and police officers and raising fears of a wave of militant violence.

On Wednesday, suspected militants killed two soldiers and wounded three others in four attacks in Sinai. In a separate incident, three suspected militants were killed when their explosives-laden car blew up apparently prematurely just outside el-Arish, a coastal city in northern Sinai that is a stronghold of Islamist radicals, security officials said, speaking on the condition of anonymity because they were not authorized to talk to the news media.

Early Wednesday, a bomb went off outside the main police headquarters in the Nile Delta city of Mansoura, wounding 19 people. Presidential spokesman Ahmed el-Muslemani called the attack an act of terrorism.

The Mansoura bombing is a possible sign that a militant campaign could be spreading to Egypt’s heartland, where the violence has been restricted to street clashes between the two sides.

A political adviser to Adly Mansour, the interim president, said that the state already has a mandate to maintain security but that the army chief is seeking additional assurance that the state and citizens are on the same side.

“We are talking about a people who are subjected to aggression on the streets,” Mustafa Hegazi said, alluding to allegations of violence by Morsi supporters against opponents.

— Associated Press