Turkey’s state-run news agency says authorities have issued warrants for the detention of 121 former Foreign Ministry employees, suspected of links to U.S.-based Muslim cleric Fethullah Gulen whom Turkey blames for last year’s failed coup attempt, New York Times reported.

Anadolu Agency says that police launched simultaneous operations Thursday in about 30 provinces to detain the ministry employees. It says the suspects were previously fired from posts as part of a vast government crackdown on suspected followers of Gulen’s movement.

Some of the suspects are believed to have used an encrypted secret messaging app allegedly favored by followers to communicate with each other, according to Anadolu.

Turkey has arrested more than 50,000 people and purged over 110,000 from government jobs in the failed coup’s aftermath.

Gulen denies involvement in the coup attempt.