Amnesty International on Wednesday accused Egypt's government of mounting a crackdown on freedom of expression that had turned the country into an "open-air prison" for critics.
The international human rights group said authorities had arrested at least 111 people since December for criticizing President Abdel Fattah al-Sisi and Egypt's human rights situation in a campaign that surpassed any under ousted President Hosni Mubarak.
"It is currently more dangerous to criticize the government in Egypt than at any time in the country's recent history," Amnesty's North Africa Campaigns Director Najia Bounaim said in a statement.
"Egyptians living under President al-Sisi are treated as criminals simply for peacefully expressing their opinions."
A government spokesman had no immediate comment on the Amnesty report when contacted by Reuters.
The security services had ruthlessly clamped down on independent political, social and cultural spaces, Amnesty said.
"These measures, more extreme than anything seen in former President Hosni Mubarak's repressive 30-year rule, have turned Egypt into an open-air prison for critics," it said.
Sisi's supporters maintain the president, who was re-elected in March, has been trying to combat an Islamist insurgency and restore order to the country following years of chaos after Arab Spring demonstrations forced Mubarak to step down in 2011.
They say that Sisi has improved security since 2013, when as army chief he ousted Islamist President Mohamed Mursi following mass protests against his rule.
Among those arrested were at least 35 people held on charges of "unauthorized protest" and "joining a terrorist group" after a peaceful protest against metro fare increases, and comics and satirists who posted commentary online, Amnesty said.
They also include prominent figures and possible presidential contenders, such as former military chief of staff Sami Anan and former presidential contender Abdel Moneim Abol Fotouh, as well as former state auditor Hesham Genena.
Amnesty said at least 28 journalists were among those detained since December 2017.
"President al-Sisi's administration is punishing peaceful opposition and political activists with spurious counterterrorism legislation and other vague laws that define any dissent as a criminal act," Bounaim said.