Turkish police arrested 34 suspects on Monday over links to the Fetullah Terrorist Organization (FETO), the group behind the 2016 defeated coup attempt, security sources said.

The arrests on charges of using ByLock, the terror group’s encrypted smartphone messaging app, came after prosecutors in the capital Ankara issued arrest warrants for 46 suspects.

Police continue seeking the remaining suspects.

FETO and its U.S.-based leader Fetullah Gulen orchestrated the defeated coup on July 15, 2016, which left 251 people martyred and nearly 2,200 injured.

Ankara also accuses FETO of being behind a long-running campaign to overthrow the state through the

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