CAIRO, Egypt -- Egyptian security forces quickly put down scattered protests Friday as an attempt by Islamists to hold the first major anti-government rallies in months fizzled, with at least two protesters and three army and navy officers killed in separate incidents.

The call for nationwide rallies to topple the government marked the first attempt in months to hold large protests in the face of a massive crackdown since the military's ouster last year of Islamist President Mohammed Morsi.

Several mosques listed as gathering points by organizers remained largely empty. Small, scattered demonstrations by a few hundred protesters were quickly quashed by security forces.

The three military officers were killed in separate shootings early Friday morning. The army officers were shot dead in Cairo while the navy officer was killed in Alexandria. After Friday prayers, two civilians were killed in the eastern Cairo neighbourhood of Matariya, where security forces clashed with protesters, according to the Health Ministry.

Security forces had vowed to use "lethal force" and maintained a heavy presence from the early morning. Armored vehicles deployed across the city while cement blocks sealed off roads leading to security headquarters, the presidential palace, the Ministry of Defence and the main Cathedral. Army helicopters hovered overhead.

Friday sermons by government-appointed clerics spoke against demonstrations. In a Cairo sermon aired on state TV, an imam said: "Don't do it ... You can't fix corruption by sabotage, terrorizing safe people, and shedding blood."

While previous demonstrations by Morsi supporters have played down their Islamist nature -- focusing instead on opposing his overthrow and restoring Egyptian democracy -- the calls for Friday's protests were overtly religious. The ultraconservative Salafi group organizing the rallies warned of a war against Islam and urged protesters to raise Qurans in the air. The theme of the demonstrations was "Muslim Youth Uprising."

Salafi Front spokesman Hisham Kamal said, "this is only a beginning" and added that turnout was satisfactory if compared to "stagnant water" of the past period.

Morsi's Muslim Brotherhood group supported the protest call but warned its supporters against being dragged into a violent confrontation.