Egyptian security forces and stone throwing youths have engaged in a third day of violence in the Suez Canal city of Port Said.
Police fired warning shots and tear gas in an attempt to disperse hundreds of demonstrators.
As least six people have been killed, including three police officers, in the latest spate of violence.
Port Said has been a tinderbox since January; when 21 people were sentenced to death after a riot at a football match left 73 people dead.
Egypt has been in turmoil since Hosni Mubarak was ousted from power in 2011.
Instability has continued following the election of his Islamist successor Mohamed Mursi.