Egypt's ruling military council apologised on Saturday after military police beat protesters in Cairo's Tahrir Square, but activists called for fresh protests to denounce violence by the authorities.
A security official and witnesses said that shortly after midnight, military police surrounded protesters, beating them with batons and using tasers to disperse the crowd of several hundred that had gathered to push for reforms.
The Supreme Council of the Armed Forces said that "what happened late Friday was the result of unintentional confrontations between the military police and the youth of the revolution."
It stressed that it "did not and will not issue orders to attack the youth, and all measures will be taken to ensure this will not happen again."
But activists launched a Facebook call for fresh protests on Saturday to denounce the army's use of force.
"Peaceful protesters in Tahrir are being chased away by the military police with tasers, sticks and whips. Masked men with machine guns trying to shut down the strike by force. Many beaten, assaulted and arrested," the statement said.
"We cannot stand for this; we must stand strong against violence towards peaceful protesters."
On Friday, thousands of Egyptians rallied in the square -- the focal point of anti-government protests that toppled president Hosni Mubarak -- to celebrate the success of their revolution and call for a new government purged of old guard remnants.
They demanded the replacement of the government of Prime Minister Ahmad Shafiq. Even after a reshuffle on Wednesday, a number of key portfolios, including foreign affairs and defence, are still in the hands of Mubarak regime veterans.
"Shafiq's government is subservient to the corrupt regime," read one banner carried by demonstrators.
Protesters also called for the abolition of the much feared state security services.
Mubarak, who resigned on February 11, handed power to the army.
The Supreme Council of the Armed Forces ordered Shafiq's government to run the country's affairs for six months "or until the end of parliamentary and presidential elections."
It has vowed to uphold the principles of the uprising and fight the corruption that tainted Mubarak's regime.