Egypt's government says clashes in central Cairo have left nearly 600 people injured.
Security forces continued to use tear gas and batons in their attempt to quell hundreds of angry, mainly young protesters demanding that trials of former officials proceed more swiftly, more than 12 hours after clashes began on June 28.
It was the first such violence for weeks in and around Tahrir Square, the center of a revolt that toppled President Hosni Mubarak in February.
The Health Ministry said more than 500 of those injured were being treated in hospital.
Up to 40 members of the security forces were among those hurt.
compiled from agency reports