Egyptian police fired tear gas to disperse opposition demonstrators hurling rocks and firebombs near Cairo’s Tahrir Square on Friday evening, official news agency MENA reported, although no casualties were reported.

Egyptian police fired tear gas to disperse opposition demonstrators hurling rocks and firebombs near Cairo's Tahrir Square on Friday evening, official news agency MENA reported, although no casualties were reported.

The protesters, including members of the Black Bloc group, began demonstrating outside the offices of the prosecutor general and set fire to the entrance to the building, before heading to Tahrir Square and blocking traffic on the Qasr Al-Nil bridge.

Satellite television station ONTV aired live footage showing security forces clashing with demonstrators on the Qasr Al-Nil bridge.

Egypt's prosecutor general had ordered the arrest of several members of the
Black Bloc, a group opposed to President Mohammad Mursi.

Demonstrators, hooded and masked and dressed in black from head to toe,
appeared in January in Cairo and other provinces, calling themselves the Black
Bloc.

They present themselves as the defenders of protesters opposed to President Mursi's rule.

On their Facebook page, the activists say they are a "generation born of the blood of the martyrs" from the 2011 revolution that toppled former President Hosni Moubarak.