An Egyptian activist who was a leader of the uprising that toppled Hosni Mubarak has been sentenced at a retrial to 15 years in prison for rioting.
Ahmed Douma was also fined $335,000 (£262,000) over his alleged role in a Cairo protest in December 2011, in which a science academy was set ablaze.
He had appealed against the 25-year sentence he was handed in 2015.
Douma has been imprisoned since 2013, when he was convicted of violating a law that banned unauthorised protests.
The law was introduced after the military overthrew President Mubarak's democratically-elected successor, Mohammed Morsi, in July 2013, and launched a crackdown on dissent.
More than 1,000 protesters were killed in clashes with security forces. Since then, at least 60,000 people are reported to have been arrested or charged, hundreds have been handed preliminary death sentences, and hundreds more have gone missing in apparent forced disappearances.
Most of them have been supporters of Morsi's Islamist movement, the Muslim Brotherhood, but liberal and secular opposition activists have also been targeted.
Douma was a founder of the now-banned April 6 youth movement, and is one of Egypt's best-known activists.
At his retrial, he faced the charges of illegal assembly, weapons possession, assaulting police and military forces, setting on fire the Institut d'Egypte, and vandalising other government property, including the cabinet and parliament buildings, according to the Mada Masr website.
Prosecutors said he was among a group of protesters who staged a sit-in to press for the resignation of then Prime Minister Kamal al-Ganzouri. At least 12 protesters were killed when security forces forcibly broke up the gathering.
His sentence was upheld on appeal in July 2017, but the Court of Cassation overturned it three months later and ordered a retrial that began last week.