Calls for US role to calm Mediterranean tensions come during a meeting between Egyptian and Greek leaders in Athens.
A prominent Egyptian rights group has said security agents have arrested its executive director, its third member to be taken into custody in less than a week despite international criticism.
“Gasser Abdel Razek was detained by security forces from his home in Maadi and taken to an unknown location,” the Egyptian Initiative for Personal Rights (EIPR) tweeted late on Thursday. It gave no further details.
On Sunday, Egyptian security forces arrested the group’s office manager, Mohammed Basheer, on charges including “joining a terror group” and “spreading false news”.
Three days later, on Wednesday, Karim Ennarah, director of criminal justice at EIPR, was arrested while vacationing in the Red Sea resort of Dahab in South Sinai.
He was taken by security officers to an undisclosed location, the group said on Twitter, adding that he was ordered to be detained for 15 days pending investigations.
The arrests come after senior diplomats visited EIPR for a briefing on the human rights situation on November 3.
EIPR said Basheer was questioned by the Supreme State Security Prosecution about the organisation’s work and a visit earlier this month to its Cairo office “by a number of ambassadors and diplomats” to discuss human rights.
Pre-trial detention can last up to two years under Egyptian law, but the period is often extended.
The United States, a close ally of Egypt, said it was “deeply concerned” by the detentions.
“The United States believes that all people should be free to express their beliefs and advocate peacefully,” the State Department’s bureau handling human rights said on Twitter.
US President Donald Trump has stood firmly behind Egyptian President Abdel Fattah el-Sisi, whom he reportedly called “my favourite dictator”, but President-elect Joe Biden has signalled he will take a firmer line on human rights.
Legislators from Biden’s Democratic Party voiced outrage at the arrests and urged Egypt to free the activists immediately.
“We cannot stay silent as human rights defenders are targeted and detained,” said Representative Mark Pocan, co-chair of the Congressional Progressive Caucus.
Rights groups estimate some 60,000 detainees in Egypt are political prisoners.
These include secular activists, journalists, lawyers, academics and Islamic scholars arrested in a sweeping crackdown on dissent under President el-Sisi.
Egypt has repeatedly denied accusations of human rights violations.
Earlier this month, Foreign Minister Sameh Shoukry insisted, during a news conference with his French counterpart Jean-Yves Le Drian, that detentions in Egypt are within legal frameworks only.
“There is no arbitrary detention, there is only detention according to the law,” he said, in response to a question by a reporter about political prisoners held in Egyptian jails.