Egyptian police cleared Islamist protesters from a Cairo mosque late yesterday, after a stand-off and exchange of fire, a security source said.
Supporters of ousted president Mohammed Mursi were dragged out of the mosque.
The clashes came on the fourth day of bloodshed between the two sides, with the government saying 173 were killed in just 24 hours. That brought the death toll to more than 750 since Wednesday, when 578 people were killed when police cleared two camps of Mursi loyalists in the capital.
Authorities said they were considering disbanding Mursi's Muslim Brotherhood group, once again outlawing a group that held the pinnacle of government power just more than a month earlier.
The stand-off at Cairo's Al-Fath mosque in central Ramses Square began on Friday, with security forces surrounding the building where Islamists were sheltering and trying to convince them to leave.
The Islamists had lined up the bodies of dozens of protesters killed in Friday's "day of rage" demonstrations inside the mosque.
Earlier yesterday, the situation turned violent, with gunmen inside the mosque trading fire with police outside.
Police stormed the mosque and members of the security forces fired tear gas. In the process they dragged seven or eight men outside. These men were then confronted by angry residents who attacked them with sticks and iron bars. Police fired in the air in a bid to disperse the mob.
Both outside the mosque and in other parts of Cairo, residents targeted those suspected of being Islamists, often for no more than wearing a beard or a veil.
Among those killed on Friday was the son of Mohammed Badie, chief of Mursi's Muslim Brotherhood. The interior ministry said it had arrested 1,004 Muslim Brotherhood "elements", and security sources said the brother of al-Qaeda chief Ayman al-Zawahiri - a Mursi supporter - was detained.
The violence has left Egypt divided as never before in recent history.
European leaders have pledged a strong response and EU foreign policy chief Catherine Ashton described the violence as shocking.
Germany said it would review ties with Cairo, and joined France and Britain in calling for EU talks on the situation, expected to take place tomorrow.
Meanwhile, a small explosion rocked the Egyptian consulate in the Libyan city of Benghazi yesterday, blowing out its windows and those of adjacent buildings. A security guard was injured.
Additional reporting by Associated Press, Reuters