About 600 prisoners broke out of a Cairo prison on Saturday after riots erupted, security officials said.
Several people were killed and wounded as the prisoners rioted and unknown assailants outside the prison fired at guards, the officials said. It was not immediately clear who the casualties were.
It was the second mass escape from the Marg prison since anti-government riots targeting police stations and several prisons erupted on January 28 alongside the popular uprising that ousted president Hosni Mubarak.
Along with police, the armed forces, now in control of the country after Mubarak stepped down on Friday, have arrested more than a thousand escaped convicts since the beginning of the month, according to officials.
Some of the escapees included Palestinian militants who broke out from Abu Zaabal prison north of Cairo, where at least 14 people, including two policemen, where killed during the breakout.