Police detained a senior official of the opposition Peoples' Democratic Party (HDP) in Ankara on Monday morning, according to a police source.
An anti-terrorism police team detained Aysel Tugluk as part of an investigation carried out by the Diyarbakir Chief Public Prosecutor's Office against the PKK/KCK terrorist group, the source, who spoke on condition of anonymity due to restrictions on talking to the media, said.
Tugluk will be sent to southeastern Diyarbakir province following a health check-up, the source said.
Also, five more suspects were detained in Diyarbakir on Monday on charges of "being a member of an armed terrorist group" and "managing an armed terrorist group", another police source said.
Last month, 13 HDP lawmakers were arrested, 10 of whom, including HDP Co-Chairs Selahattin Demirtas and Figen Yuksekdag, remain in custody awaiting trial on terrorism-related charges.
The lawmakers face prosecution under anti-terrorism legislation after their parliamentary immunity was lifted earlier this year.
The government has accused the HDP of having links to the PKK, which is listed as a terrorist organization by Turkey, the U.S., and EU.