Egyptian TV showed protesters clashing with security forces, with army vehicles burning outside the state television building.

Christian Copts blame Muslim radicals for the partial demolition of a Coptic church in Aswan province last week. Sectarian tensions have increased since President Hosni Mubarak was ousted in a popular uprising in February. This was the worst violence in Egypt since then.

Egypt's Coptic Christians - who make up about 10% of the population - accuse the governing military council of being too lenient on the perpetrators of a string of anti-Christian attacks.

Prime minister Essam Sharaf appealed to Egyptians not to give in to sectarian strife, the AFP news agency reported.  "What is taking place are not clashes between Muslims and Christians but attempts to provoke chaos and dissent," he said on his Facebook page, according to AFP.

Protesters on Sunday were calling on the council to sack the governor of Aswan province after the church was damaged on Friday.

The clashes began outside the state TV building in central Maspero Square but soon spread to Tahrir Square, the epicentre of the demonstrations which led to President Mubarak's resignation. Thousands joined in the street violence, hurling stones and tearing up the pavement for ammunition.

It is not clear how many of those killed were soldiers and how many were demonstrators. Protesters also called for the resignation of the military council, in particular its chairman, Field Marshal Mohamed Tantawi.

The BBC's Yolande Knell, in Cairo, says sectarian tensions have simmered in the political and security vacuum that has developed in the past couple of months.

As well as the clashes between police and protesters, other groups of thugs were also involved, our correspondent says - part of the pattern of sectarian violence in Egypt.

Thousands joined the initial march from the Shubra district of northern Cairo to the state TV building where they intended to hold a sit-in. But they said they were assaulted by attackers in plain clothes before the clashes with the security forces broke out.

This latest violence comes ahead of parliamentary elections scheduled for 28 November, the first such vote since President Mubarak stepped down.

BBC