Amnesty International’s Belgium director, Philippe Hensmans, posed in a cage in front of the Turkish Embassy in Brussels earlier this month to protest the detention of his Turkish counterpart, Idil Eser. (Francois Lenoir/Reuters)

A Turkish court on Tuesday ordered the formal arrest of Amnesty International’s Turkey director and five other human rights workers in a sign of what rights advocates say is the government’s growing intolerance of critical voices.   

The Amnesty director, Idil Eser, was detained along with nine other human rights advocates this month during a raid on a hotel where the group was attending a workshop. Amnesty said in a statement that the rights workers “are suspected, without grounds, of ‘committing crime in the name of a terrorist organization without being a member.’ ”

Four members of the group were released on bail Tuesday but remain under investigation, Amnesty said. “This is not a legitimate prosecution,” Salil Shetty, Amnesty’s secretary general, said in a statement. “This is a politically motivated persecution that charts a frightening future for rights in Turkey.”

The government of President Recep Tayyip Erdogan has arrested more than 50,000 people in the year since an attempted coup by renegade soldiers last July, according to Justice Ministry figures. Tens of thousands of people have also been dismissed or suspended from their jobs. Authorities have said their campaign is aimed at followers of Fethullah Gulen, an exiled cleric whom authorities have called the mastermind of the coup attempt, as well as at Kurdish militants. 

During ceremonies Saturday commemorating the coup attempt, Erdogan promised that the state’s hunt for its enemies would continue, vowing that “none of the traitors who betrayed this country will remain unpunished.” 

Human rights groups including Amnesty have said that the arrests and purges since the coup attempt have swept up ordinary dissidents, critics or innocent citizens. In a recent Amnesty report, some people dismissed from their jobs said they had fallen under scrutiny because of union activism or had been the victims of score-settling. 

About two weeks after the release of that report, Turkish police arrested Taner Kilic, Amnesty’s Turkey board chairman, and charged him with being a member of Gulen’s organization. 

 As part of its campaign to protest the arrests this month, Amnesty called attention to its past advocacy on behalf of Erdogan, who was jailed in 1998 when he was the mayor of Istanbul for reading a poem at a demonstration. The organization said it had written a letter to the Turkish government demanding Erdogan’s release, had declared him a prisoner of conscience and “launched a global campaign on his behalf.” 

 In a comment on the arrests, Erdogan questioned why the human rights workers had been gathering at the hotel and linked their meeting to the “continuation of July 15,” the day of the attempted coup.  

Andrew Gardner, a Turkey researcher for Amnesty, said his colleagues had been attending a workshop focused on digital security and “ ‘resilience’ — essentially being a rights defender in difficult circumstances.” Those arrested Tuesday included two foreign nationals: a Swedish citizen and a German citizen who were the workshop trainers.