The first hearing of a trial on the Gülenist Terror Group's (FETÖ) influence in the media got underway on Monday in Istanbul.Twenty-nine defendants accused of pro-FETÖ propaganda, including Atilla Taş, a former pop singer turned columnist, face prison terms of up to 22 years on charges of membership to a terrorist group, and aiding and abetting a terrorist group.Two defendants are being tried in absentia, including Said Sefa, a journalist who is accused of setting up notorious FETÖ-linked Twitter phenomenon "fuatavni."The terrorist group, which faces a new barrage of trials after the July 15 coup attempt, its latest bid to seize power through its infiltrators, is accused of running media outlets to vindicate its actions and orchestrating defamation campaigns against the cult's critics.Several lawmakers from the opposition Republican People's Party (CHP), whose members have been a fixture in trials against FETÖ, watched the trial open at the 25th High Criminal Court in Istanbul's Çağlayan courthouse complex.Defendants range from Atilla Taş, a pop music singer who took to writing pro-FETÖ pieces in recent years, to Gökçe Fırat Çulhaoğlu, who ran a far-left publication that opposed Turkey's crackdown on the terrorist group.Said Sefa, a journalist accused of setting up Twitter phenomenon "fuatavni" account, is also among the defendants. Sefa remains at large, along with another defendant.Fuatavni was a purported whistleblower that disseminated confidential information regarding the inner workings of the presidential complex in Ankara and often hurled insults and threats against President Recep Tayyip Erdoğan.The Twitter account went silent shortly after the coup attempt, which was foiled thanks to a strong public resistance.President Erdoğan had managed to escape an assassination bid during the July 15 coup attempt with just minutes to spare.Prosecutors are calling for life imprisonment for Said Sefa on charges of "attempting to overthrow the government" and lower prison terms for running "an armed terrorist group," in reference to the coup bid and FETÖ's other crimes.Atilla Taş and Ünal Tanık, who both run a pro-FETÖ news website, as well as a number of journalists who worked at FETÖ-linked media outlets, face prison terms from seven to 15 years for membership to a terrorist group.The trial in Istanbul is among a number of legal proceedings against FETÖ's media arms.More trials are expected to start later this year as prosecutors draft the indictment against journalists and newspaper executives who worked at media outlets linked to the group.The terrorist group once wielded considerable clout in the media where it ran a broadcaster. The group owned several TV stations, a publisher behind newspapers and magazines that disseminated the group's propaganda and several radio stations.Most were closed down as part of the crackdown on FETÖ and were handed to trustees as the legal process against FETÖ members got underway.The media was key for Fetullah Gülen, the U.S.-based leader of the terrorist group, to spread his messages to his followers.Gülen, who faces extradition from the United States, is already implicated in a string of criminal cases from the coup attempt carried out by his followers in the army, to sham trials against his critics.Defendants in the Istanbul trial are known for their fierce criticism of operations against the terrorist group.Since December 2013, when FETÖ emerged as the perpetrator of two coup attempts against the government, FETÖ has been regarded as a security threat. Prosecutors are claiming that the group's infiltrators in law enforcement, judiciary, bureaucracy and the military, had waged a campaign to topple the government.