A large banner cursing US-based Islamic scholar Fethullah Gülen and his followers has been hung on the front facade of Atatürk Culture Center, a historic building overlooking İstanbul’s famed Taksim square.

The banner read, “The dog of Satan, Feto. We will execute you and your fallowers with your own leash.” According to several media outlets, the banner was hung by people from the Justice and Development Party (AK Party) İstanbul provincial branch.

FETO is an abbreviation used for the Gulen Movement, which the ruling Justice and Development Party (AKP) says was behind the July 15 failed coup attempt.