|Protesters accused soldiers clearing the square of using excessive force [EPA]
The Egyptian army has forcefully removed protesters from Cairo's Tahrir Square, after dozens of men armed with rocks attacked several hundred pro-reform campaigners.
Officers fired warning shots in the air to break up the two sides on Wednesday and scores were arrested. The flow of traffic through the square was cut off but has since been restored.
"We were attacked by the army and plainclothes thugs destroying the tents and beating up everyone," Salma Said, one of the pro-reform campaigners, said.
"I was very shocked seeing the army coming with sticks, beating everyone and destroying tents over people's heads."
Activists said they had caught one man who said he had been paid to attack the protesters.
"I saw two people injured in the head, carried away by people," Ahmed Fathy, a witness, said.
Amnesty International, a London-based human rights group, condemned the army's "heavy-handed actions" in clearing the square of protesters.
"It is absolutely unacceptable that the army should participate in violently breaking up the peaceful protests", Hassiba Hadj Sahraoui, Amnesty International's deputy director for the Middle East and North Africa, said.
"The Supreme Military Council has the duty to uphold the right to peaceful protest.
"We have spoken to eyewitnesses who have told us that the army allowed thugs to attack protesters with sticks and swords, the same practice that was used under former president [Hosni] Mubarak.
"It appears that the Armed Forces are simply continuing the same old tactics of repression."
Small groups of activists had continued to gather in Tahrir Square after Hosni Mubarak, the former president, was toppled on February 11.
Numbers have climbed on Fridays when activists have called for bigger participation to keep up pressure on the country's leaders for political reform.
In another development, clashes that broke out late on Tuesday night when a Muslim mob attacked thousands of Coptic Christians protesting against the burning of a Cairo church have left at least 13 people dead and about 140 wounded, officials said.
The Muslims torched the church amid an escalation of tensions over a love affair between a Muslim and a Copt that set off a violent feud between the couple's families.
The officials said all 13 fatalities, at least six of them Coptic Christians, died of bullet wounds.
There is a long history of animosity between Copts and Muslims in Egypt, though there have been recent signs of a rapprochement following a deadly New Year's Day bombing of a church in Alexandria.