CAIRO - Protesters demanding Egypt's ruling generals hand over power beat back a new police raid to evict them from Cairo's central Tahrir Square on Monday, witnesses said.
The police fired tear gas and attacked a makeshift field hospital, said the witnesses.
They said the protesters broke up pavements to hurl the chunks of concrete at police.
At least 12 people have been killed in clashes between government forces and protesters in Cairo and other cities since Saturday in some of the worst violence since the overthrow of Hosni Mubarak.
Tahrir Square was the major rallying point for protesters in Cairo when an 18-day uprising toppled Hosni Mubarak from three decades of power in February.