CAIRO (AP) — The family of a leading Egyptian pro-democracy activist, who was arrested amid a recent clampdown following anti-government protests, says he was beaten, threatened and stripped to his underwear while in custody.

Mona Seif, a prominent human rights activist tweeted on Thursday that her brother Alaa Abdel-Fattah also told his lawyers he was blindfolded and threatened that he would never set food outside one of Cairo's most notorious prisons.

Abdel Fattah, who rose to prominence with the 2011 uprisings that swept the Middle East and in Egypt toppled long-time President Hosni Mubarak, was among more than 2,900 people who activists say were arrested since September protests demanding President Abdel-Fattah El-Sissi step down.

Earlier, Abdel-Fattah was released in March, after five years in prison for taking part in a peaceful protest.