The Welt daily said on its website that Deniz Yucel, who has both Turkish and German citizenship, went to police offices in Istanbul to face questioning and that his apartment had been searched. The paper said police accused him of membership in a terrorist organization, misuse of data and terrorist propaganda.
Yucel, 43, had reported on emails that were obtained by the leftist hacker collective RedHack from the private email account of Energy Minister Berat Albayrak and made available on WikiLeaks, the paper said. Subjects included influencing public opinion through fake Twitter accounts and the control of Turkey media companies. Other journalists have also written about the emails.
Albayrak is a son-in-law of President Recep Tayyip Erdogan. Editor-in-chief Ulf Poschardt said Yucel "does excellent work" and that "we trust that fair proceedings will prove his innocence." Germany's Foreign Ministry said Yucel has been in police detention since Tuesday "in connection with a criminal investigation."
"We hope the ongoing investigation by Turkish authorities against Mr. Yucel respects the rule of law and he is treated fairly, in particular with regard to the press freedom that's guaranteed by the Turkish constitution," the ministry said in a statement, adding: "Of course we are doing everything we can to support Deniz Yucel."
According to the Committee to Protect Journalists, a nonprofit press freedom group based in New York, at least 81 journalists were imprisoned in Turkey last year — the biggest number worldwide. Many of the arrests came following a July 15 coup attempt that prompted a government crackdown on alleged anti-government activists that included the closure of at least 100 news outlets.
This story corrects Erdogan's title from prime minister to president.