Egypt's security services have forcibly made hundreds of people disappear and tortured them in the past year to try to tackle dissent, a rights group says.
Students, political activists and protesters - some as young as 14 - have vanished without a trace, according to a new report by Amnesty International.
Many are alleged to have been held for months and often kept blindfolded and handcuffed for the entire period.
Egypt's government has denied it uses enforced disappearances and torture.
Interior Minister Magdy Abdul Ghaffar has insisted the security services operate within a framework established by Egyptian law.
More than 1,000 people have been killed and 40,000 are believed to have been jailed since President Abdul Fattah al-Sisi led the military's overthrew of Mohammed Morsi, Egypt's first democratically-elected head of state, in 2013.
Amnesty's Middle East and North Africa director, Philip Luther, said enforced disappearances had become a "key instrument of state policy" under Mr Sisi and Mr Abdul Ghaffar, who took office in March 2015.