Scores of people have been killed in Egypt after security forces opened fire on anti-coup protesters staging a "day of rage" against the military-led government.

In the worst of the violence on Friday, at least 95 people were killed and hundreds injured in Cairo's Ramses Square as anti-coup protesters were fired on by government forces. A correspondent for Al Jazeera described lines of bodies in a makeshift morgue in the nearby Al-Fath mosque.

A protester, Said Mohammed, told Al Jazeera that the crowds were shot at by snipers and by men in helicopters.

"Helicopters started to shoot us as we were walking. Not bombs this time, it was bullets. My friend took a shot in the neck and he died," he said. "This was the first time we saw helicopters shooting. There were people shooting from the windows."

Earlier on October 6 bridge near Ramses Square, a protester called Ahmed Tohami told Al Jazeera that police were firing at marchers.

"Men, young ladies, old women, under attack. The kids here on the bridge - we are under attack... there is no way down. They are attacking us from the front, they are attacking us from behind. We have nowhere to go," he said live on Al Jazeera.

Also in Cairo, residents blocked roads and clashed with anti-coup protesters as they tried to move through their areas. Ambulances carrying injured from the Ramses Square clash were also forced back.

Later in the evening, witnesses inside the Al-Fath mosque told Al Jazeera that police, soldiers and "thugs" were attempting to storm the building and that there were hundreds of people inside, including women and children. Live footage appeared to show tear gas being fired into the building.

"They are entering with guns. They are threatening to burn the mosque with the people in it," Umayma, a protester inside the mosque, told Al Jazeera in a telephone interview.

In Alexandria, 21 people were reported dead in clashes between pro- and anti-coup supporters. Al Jazeera's Jane Ferguson reported bands of men armed with batons and machetes on the streets as night fell.

Elsewhere, eight protesters were killed in the city of Damietta, while four died in Ismailia, northeast of Cairo.

Bader Abdel Atty, a spokesman for the Egyptian foreign ministry, defended the actions of the security forces in an interview with Al Jazeera, saying that protesters were armed with machine guns.

"They are raising al-Qaeda flags in the heart of Cairo. They are using machine guns against civilians. And this cannot be described as far as I know as a peaceful demonstration," he said.

He dismissed international condemnation of the violence and said it was not based on the facts.

The Muslim Brotherhood and other groups, under the banner of the Anti-Coup Alliance, had called for the protests on Friday in defiance of a military crackdown on sit-in demonstrations that left hundreds dead on August 14.

Casualty figures Ramses Square, Cairo: 95 reported dead, hundreds injured. Damietta: Eight reported killed. Alexandria: 21 dead as pro- and anti-Morsi groups clash. Ismailia: Four reported killed.

A curfew came into effect at 5pm GMT, with authorities warning "firm action" against breakers.

In a statement, the interim Cabinet asserted that the government, the police and the "great Egyptian forces" stood together in the face of a "brutal terrorist plot" by the "Brotherhood organisation".

The Brotherhood in turn said the coup leaders had "lost their minds" and were devoid of ethics and values. It said the coup had failed, and called for a week of daily marches in defiance of the crackdowns.