Three district mayors from the pro-Kurdish Peoples’ Democratic Party (HDP) in the eastern province of Bitlis who were detained on Dec. 14 as part of a terrorism probe were arrested on Wednesday.

With the arrest of the co-mayors, the total number of those behind bars is now 67.

Hizan Mayor İhsan Uğur, Mutki Mayor Özcan Birlik and Yolalan Mayor Felemez Aydın were detained as part of an operation against the outlawed Kurdistan Workers’ Party (PKK) and the Kurdistan Communities Union (KCK), according to a statement from the Bitlis Governor’s Office.

They appeared before a court on Wednesday where they were subsequently arrested on charges of membership in a terror organization, involvement in activities on behalf of a terror organization and aiding and abetting a terror organization.