Detention warrants were issued for 18 teachers in Turkey’s Ankara as part of a post-coup investigation into the Gulen movement, on Tuesday.

The suspects are accused of using Bylock, an encrypted mobile app that Turkish government sees as a communication tool among followers of the Gulen movement.

Three out of 18 were detained at the time of writing.

Turkish government accuses Gulenists of masterminding the July 15, 2016 failed coup while the group denies involvement. Interior Minister Suleyman Soylu said in March, 2019 that at least 510,000 people have been detained over Gulen links since the summer of 2016.