Interim Prime Minister Hazem El Beblawi of Egypt has defended the actions of the security forces against the Muslim Brotherhood.
In an interview with the ABC TV network, he said that everyone was unhappy about the loss of life, but the government had no choice when its authority was challenged in the streets.
He also defended the arrest of Muslim Brotherhood leader Mohammad Badie on charges of murder and inciting violence.
Mr Badie, 70, was detained in a flat in Nasr City in north-east Cairo early on Tuesday. His son Ammar, 38, was killed last week.
The BBC reports almost 900 people have been killed across the country since Wednesday. Egypt is under a state of emergency.
A Brotherhood spokesman said the arrest was part of a plot against the 2011 revolution that ousted Hosni Mubarak.
Mr Badie has reportedly been temporarily replaced as "general guide" by the movement's deputy leader, Mahmoud Ezzat. He is also subject to an arrest warrant.
On Tuesday the Brotherhood urged its supporters to continue protests demanding the reinstatement of Mr Morsi.
In another development on Tuesday, the BBC reports former interim vice president Mohamed ElBaradei is to face trial on charges of breaching national trust.
Mr ElBaradei, who is now out of the country, resigned on 14 August after security forces dispersed two protest camps in Cairo set up by supporters of President Mohammed Morsi who was deposed by the Army on 3 July.
The prosecutor general acted after receiving a complaint, saying Mr ElBaradei's action gave the impression that the government had used excessive force.
Military aid
Mr Beblawi also told ABC News that any decision by the United States to cut military aid to Egypt "will be a bad sign - it will definitely affect the military for some time". But he said Egypt's army would survive.
''Don't forget the Egyptian people went with Russian military aid for decades so there are ways that someone can survive," he said.
