Automatic weapons have been fired at the anti-government protest camp in the Egyptian capital in a dramatic escalation of what appeared to be a well-orchestrated series of assaults on the demonstrators.
At least three protesters were killed by gunfire in Cairo’s Tahrir Square, according to the activists.
The crowds seeking an end to Hosni Mubarak’s nearly three decades in power were still reeling from attacks hours earlier in which Mubarak supporters charged into the square on horses and camels, lashing people with whips, while others threw firebombs and rocks from rooftops.
The protesters accused Mr Mubarak’s regime of unleashing a force of paid thugs and plain-clothes police to crush their unprecedented nine-day movement, a day after the 82-year-old president refused to step down.
The protesters showed police ID badges they said were wrested from their attackers, while some government workers said their employers ordered them into the streets.
The violence intensified overnight as sustained bursts of automatic gunfire and single shots rained into the square, starting at around 4am and continuing for more than two hours.
Protest organiser Mustafa el-Naggar said he saw the bodies of three dead protesters being carried towards an ambulance. He said the gunfire came from at least three locations in the distance and that the Egyptian military, which has ringed the square with tanks for days to try to keep order, did not intervene.
Hours after the shooting ended, the army, which protesters have criticised for failing to protect them, moved four tanks to clear a highway overpass from where supporters of Mr Mubarak had been hurling rocks and firebombs on to the protesters.
It was not immediately clear if the steps were part of a wider decision for the army to begin protecting the demonstrations. TV footage appeared to show two more dead bodies being dragged along the highway overpass where the Mubarak supporters were massed.
At daybreak, the two sides were still battling with rocks and petrol bombs along the front line on the northern edge of the square, near the famed Egyptian Museum.