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.
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.