9.38pm BST

The Guardian's live coverage is now coming to a close. Here's Patrick Kingsley and Martin Chulov's report from Cairo:

New violence erupted in central Cairo and across Egypt on Friday on a "day of rage" called by the Muslim Brotherhood to protest against the removal of President Mohamed Morsi and the killings of hundreds of his supporters by the military-backed government.

By nightfall, at least 20 and as many as 45 people had been reported shot dead in fierce street fighting in the centre of the capital, where machine gun fire was heard as a military helicopter flew overhead. Security officials in Egypt said the death toll rose to at least 60 people killed across the country, 52 civilians and eight police officers. The latest death toll also included eight people confirmed killed in Damietta, four in Ismailia, and 13 elsewhere in the country.

TV cameras caught unidentified gunmen in civilian clothes firing automatic rifles on the May 15 bridge that crosses Zamalek in the heart of Cairo, where many foreigners and wealthy Egyptians live. People jumped off the bridge to escape the shooting. Uniformed police were nowhere to be seen. Firing also broke out outside a luxury hotel on the banks of the Nile near Tahrir Square.

On Friday night the Brotherhood called on its supporters to continue daily protests across the country, but it urged its supporters to protest peacefully. "The struggle to overthrow this illegitimate regime is an obligation," it said in a statement.

The interior ministry had warned that security forces had been authorised to fire live ammunition at anyone targeting police and state institutions.

The Guardian saw dozens of bodies lying on the bloodstained floor of Cairo's al-Fath mosque on Ramses Square, which had been turned into a field hospital – though medical volunteers were soon overwhelmed by the scale of the blood-letting.

Gehad al-Haddad, a Brotherhood spokesman, denounced what he called "military coup criminals" after the group said that 45 people had been killed in Ramses Square and urged supporters to withdraw to avoid further casualties.

On another day of high drama and now routine bloodshed, it was often hard for observers to keep up with the sheer pace of events. "It's impossible to follow up on everything that is taking place," tweeted commentator Bassem Sabry. "It is happening too fast, and everywhere."