Egypt's ruling military council warned on Saturday that troops would clear protesters from central Cairo's Tahrir Square with "firmness and force" if they continued to demonstrate there.
A senior military officer told reporters that the early-morning clashes had been sparked by "elements that backed the counter-revolution," a reference to those loyal to deposed President Hosni Mubarak and his ruling National Democratic Party.
"Tahrir Square will be emptied of protesters with firmness and force to ensure life goes back to normal," Major General Adel Emarah said.
Yet hundreds of protesters remained in the square overnight, through the military-enforced 2am to 5am curfew hours, and appeared to have been unharmed. There were no reports of action by army or central security forces.
Crowds of protesters retook the iconic square - the heart of the 18-day uprising that ousted Mubarak in February - hours after security forces violently dispersed them.
In scenes reminiscent of the revolution, protesters and riot police threw rocks at each other, and security forces responded by firing tear gas, witnesses said.
Groups of protesters rallying around the southeast corner of the square threw bottles and possibly petrol firebombs at riot police, Michelle May, a freelance journalist, told Al Jazeera.
Egypt's health ministry said that one person was killed and 71 injured, though the military had earlier denied that anyone was hurt or killed in the raid of the square. Emarah claimed the army had not fired at protesters, but nearly non-stop gunfire could be heard in videos of the clash and during phone conversations Al Jazeera had with witnesses in the square.
Army and central security troops withdrew later in the morning, leaving the square to protesters who began setting up barricades made of furniture and left-behind barbed wire.
"The number of protesters remaining in the square is swelling, as news [of the clashes] spreads through the city," reported Mike Hanna, Al Jazeera's correspondent in Cairo.
Army officers joined protest
Hundreds of soldiers and security troops backed by armoured vehicles stormed into the square at around 3am, firing shots into the air, brandishing tasers and batons, and beating people, witnesses said.
|YouTube user Kikhote posted this video showing army officers breaking through lines of protesters to tear down tents, with automatic gunfire
audible in the background
Tens of thousands of protesters had come to the square on Friday in one of the largest demonstrations since Mubarak stepped down on February 11.
The protesters called for the Supreme Council of the Armed Forces, which nows runs the country, to honour their demands, which include prosecuting a number of former high-ranking regime officials and Mubarak himself.
The protesters had been joined by perhaps as many as 20 military officers, who had been under orders not to participate. Demonstrators stayed in the square past the military curfew, saying they wanted to protect the officers who joined.
When security forces stormed the square, some of the protesting army officers managed to escape, while at least seven officers were arrested, witnesses said.
Loai Nagati, a student, told Al Jazeera that military police and central security forces took some protesters and beat them, but that nobody had been shot. Speaking while gunfire echoed in the background, he said that some of the army officers who joined the protests had been arrested by security forces.
Amr Bassiouny, who was standing at the square's south entrance near the old campus of the American University in Cairo, told Al Jazeera that hundreds of soldiers backed by eight armoured vehicles entered the square from that direction at around 3am.
For 10 or 15 minutes, the protesters and soldiers faced each other, said Sanaa Seif, who had been in the square since 11pm. Protesters chanted "Peaceful, peaceful," and "The people and the army, hand in hand," shes said.
The soldiers formed a semi-circle around the south end of the square and advanced towards a tent in the middle where the protesting army officers had been kept, firing "non-stop" into the air, she said. They could be seen tearing down the tent in an amateur video posted on YouTube.
Other central security and army forces had been stationed to the north of Tahrir Square next to the Egyptian Museum, which military police have turned into a makeshift detention centre. They advanced into the square in coordination with the troops to the south.
Guns fired, rocks thrown
Most of the protesters retreated after the army entered the square, witnesses said. Bassiouny ran to the west side of the square, which leads to Kasr el-Nil Bridge, and found more troops entering from that direction.
|Protesters ringing the central 'garden' in Tahrir Square faced off with soldiers before the troops advanced
On the road leading east into the central business district around Talaat Harb Square, protesters tore down the roof of a bus stop and dragged it down the road to protect themselves from gunfire and rocks, said Drew Storey, a neighbourhood resident.
Protesters and army soldiers threw rocks at each other, and at least four injured protesters had to be carried away, he said. Soldiers fired their guns into metal shopfronts, sending sparks flying and bullets ricocheting, apparently to scare away the protesters, Storey said.
At one point, he said, security forces clad in riot gear chanted, cheered and shook each others' hands after driving the protesters away.
Arbitrary arrest allegations
In recent weeks, activists have accused the army of making arbitrary arrests, abusing and torturing prisoners, and subjecting detainees to rapid military justice - all complaints that had fuelled mass anger against Mubarak's government.
The increasingly icy relationship between the ruling military council and the youth-driven protest movement was one reason many had returned to the square on Friday. But as the protest thinned and only a few people remained, demonstrators vowed to protect the army officers who had joined them, using loudspeakers to urge others to defend the soldiers with their lives, Seif said.
Though some of the protesting army officers were reportedly arrested, seven or eight escaped the square, Bassiouny said. They had been wearing uniforms, and protesters gave some of them civilian clothes to disguise themselves as they fled, he said.