Egyptian security forces used live ammunition to disperse supporters of ousted president Mohamed Morsi on 6 October, Amnesty International has said.
The human rights watchdog said that some 49 people were killed and hundreds wounded in Cairo, as security forces used excessive and unwarranted lethal force" to disperse pro-Morsi crowds.
According to news24, the Egyptian health ministry said at least 57 people were killed nationwide on the day of the bloody crackdown.
Amnesty said that security forces stood by as men in civilian clothing used firearms, knives and swords to attack the Islamist demonstrators.
On 6 October, security forces clashed with pro-Morsi crowds in Cairo as they tried to reach Tahrir Square where supporters of the military were celebrating the 40th anniversary of the Arab-Israeli war.
Amnesty's Hassiba Hadj Sahraoui said that though some pro-Morsi protesters threw rocks, burned tyres and used fireworks against security forces, they in turn resorted to the use of lethal force when it was not strictly necessary.
Amnesty said no members of the security forces were killed during the clashes.