World Bulletin / News Desk
The figure includes at least 30 deputy divisional chiefs based at the city’s police headquarters, the source said on condition of anonymity due to restrictions on speaking to the media.
The warrants were issued by Istanbul Chief Public Prosecutor's Office against those thought to have used the ByLock messaging app. Last week warrants were issued for 166 officers around the country over similar suspicions.
ByLock is said to have been used by members of the Fetullah Terror Organization (FETO), which the government has said was behind the attempted takeover.
The app is believed to have been cracked by Turkish security agencies before the coup, prompting the plotters to switch to using the WhatsApp messaging service but not before tens of thousands of FETO suspects had been identified.
Turkey accuses FETO, which is led by U.S.-based Fetullah Gulen, of organizing the defeated coup as well as a long-running campaign to overthrow the state through the infiltration of Turkish institutions, particularly the military, police and judiciary.