The Ankara Chief Public Prosecutor’s office on Tuesday issued detention warrants for 20 gendarmes as part of an investigation into Turkey’s Gülen group.

According to the state-run Anadolu news agency, while 17 of the suspects were on active duty, three had earlier been dismissed after administrative inquiries.

The Turkish government blames the Gülen group for orchestrating a 2016 coup attempt. The group denies any involvement.

Since the failed coup some 16,000 military personnel have been dismissed over Gülen links, Turkey’s defense minister said on March 29.