Anti-government demonstrations have swept across Egypt despite a 6 am-7 pm curfew imposed by the state and a vow by President Hosni Mubarak to get tough with protesters demanding his ouster.

According to a live stream on Al Jazeera’s English language website, fires are burning across Cairo. (Egypt has reportedly shut down access to Al Jazeera in the country).

The headquarters of the ruling National Democratic Party (NDP) is on fire, reports Al Jazeera.

Following midday prayers, tens of thousands of Egyptians fanned out across streets in Cairo, Suez and Alexandria and other cities, resulting in some cases in violent clashes with policemen. Security forces have reportedly fired rubber bullets and teargas at protesters.

Mohamed ElBaradei, the former head of the United Nations' nuclear watchdog and an opposition leader in Egypt, returned to his native homeland yesterday, but was placed under house arrest at his home on the outskirts of Cairo.

The Associated Press reported that an elite special counterterrorism force had been deployed at strategic points around Cairo.

This is a revolution, one 16-year-old protester in Suez told Al-Jazeera. Every day we're coming back here.

Like in many other countries in the region, protesters in Egypt complain about surging prices, unemployment and the authorities' reliance on heavy-handed security to keep dissenting voices quiet.

Egyptians torched a police post in Suez early on Thursday in response to the killing of three demonstrators earlier in the week, a Reuters witness said.

On Wednesday evening, people in Suez had tried to burn down a government building, another police post and a local office of Egypt's ruling party before police stopped them. The government has said it intervened there against what it called 'vandalism'.

A page on Facebook announcing Friday's protest gained 55,000 supporters in less than 24 hours and the call was then repeated by some opposition groups.

Egypt's Muslims and Christians will go out to fight against corruption, unemployment and oppression and absence of freedom, wrote an activist on Facebook, which alongside sites like Twitter have been key tools to rally people onto the streets.

Egypt's stock exchange halted trading on Thursday morning after the benchmark index slid more than 6 percent for a second day. The prices of two London-listed stocks focussed on Egypt also tumbled. The Egyptian pound has fallen to its lowest level in six-years against the U.S. dollar.