Thousands of inmates have escaped from prisons across Egypt, including one that housed Muslim militants north-west of Cairo, security officials said.
The developments add to the chaos engulfing Egypt as anti-government protests continue.
The officials said the prisoners escaped overnight from at least four jails after starting fires and clashing with guards.
They said that several inmates were killed and wounded during the escape, but gave no specific figures.
Residents have formed neighbourhood protection groups, armed with firearms, sticks and clubs to ward off looting gangs roaming Cairo and other cities.
Looting and arson continued overnight as the police totally disappeared from the streets of the capital and several major cities. There has been no explanation for why the police have vanished.
The army, meanwhile, is reinforcing its presence on the streets of Cairo, but entire neighbourhoods remained without any troops two days after long-time authoritarian President Hosni Mubarak called the army out on the streets to restore order.
Groups of youths also directed traffic in parts of Cairo, chasing away gangs of criminals smashing passing cars. Residents said gangs were also stopping people on the streets and robbing them.
State Egyptian television, meanwhile, said authorities have decided to close down the Cairo offices of the Qatar-based Al-Jazeera television and suspend the accreditation of its reporters.
The Egyptian TV did not give a reason for the move, but Egyptian authorities have often in the past claimed the station’s coverage of events in Egypt was sensational or biased against Mubarak’s regime.