Tens of thousands rallied in Cairo's Tahrir Square on Friday, trying to keep up pressure on Egypt's military rulers to carry out reforms and calling for the dismissal of holdovers from the regime of ousted President Hosni Mubarak.

The downtown square had been the center of an 18-day uprising that brought down Mubarak on Feb. 11. The Egyptian military took over from Mubarak, but assigned government affairs to a caretaker Cabinet until elections can be held.

Demonstrators said Friday they are worried the army is not moving quickly enough on reforms, including repealing emergency laws, releasing political prisoners and removing members of Mubarak's regime from power.

Thousands chanted Friday that they won't leave until they see Prime Minister Ahmed Shafiq, one of the Mubarak-era holdovers, removed from office. Some waved flags of Libya to show support for the uprising in the North African country next to Egypt.

"We made Mubarak step down and we must make Shafiq also step down," said Safwat Hegazy, a protester from the Muslim Brotherhood, Egypt's largest and best-organized opposition group.

Demonstrators said they would stage large rallies every Friday until their demands are met.

Protester Wael Hassan, 32, said he felt much still needs to be done to ensure change.

"Mubarak is still free and moving around. His sons and his wife and the members of his regime are still moving freely, except for a few scapegoats," he said by phone from the square.

He said he is skeptical about the military's resolve to fulfill all the protesters' demands, adding that the military benefited from the old regime. "It's the people who have to force the army to change. If we leave it to the army, we'll be back to dictatorship again," he said.

Since Mubarak's fall, the military rulers have disbanded both houses of parliament and promised constitutional reforms that will allow wider participation in elections, to be held within six months. They have also promised to repeal emergency laws that give security forces largely unchecked powers, though only when conditions permit — a caveat that worries protesters.

Authorities have also moved against members of Mubarak's regime, arresting a number of former ministers and prominent businessmen on corruption allegations.

Some two dozen ex-ministers and business leaders are under investigation. Protesters have often mentioned corruption as a key motive behind their movement.

Friday's crowd also performed Muslim prayers in the square. In a sermon to the worshippers, Sheik Mohammed Jibril called for the dissolution of Mubarak's National Democratic Party, Egypt's official Middle East News Agency said.

He said God had helped the uprising bring down bad rulers.

Also Friday, a military court sentenced 13 policemen to five years in prison each for taking part in an attack on a security building in Cairo, said security officials speaking on condition of anonymity because they were not authorized to speak to the media.

The sentence came just two days after hundreds of low-ranking police officers set fire to parts of the security headquarters, pressing demands for better pay.