Egyptian rights activist Gamal Eid has been prevented from travelling after attempting to board a flight from Cairo to Athens on Thursday morning.
"In a law-respecting country, a citizen is accused, investigated, and then banned from travel. In Egypt and other police states, they are banned from travel without being told why," Eid said in a tweet following his ban.
Security officials informed Eid, a lawyer and manager at the Arabic Network for Human Rights Information, of his travel ban after his name appeared on a no-fly list while he was going through airport security.
The officials later said that the ban was due to a decision taken by Egypt's top prosecutor, who had restricted the activist from travelling because of his involvement in an ongoing trial.
The travel ban on Eid comes amid a wave of increasing restrictions that have been placed upon Egyptian activists by national security agencies.
Earlier this week, airport security prevented political activist Atef Botros from entering Egypt from Germany. He was later deported after questionining.
According to a report published by Human Rights Watch on November 1, at least 32 passports of activists and NGO workers were seized last year by Egyptian airport security officials, with many still awaiting the return of their official documents.
"The Egyptian authorities have jailed thousands of dissidents in the past two years and are now turning the country's own borders into de facto prison walls," said Nadim Houry, Human Rights Watch's deputy Middle East and North Africa director.