Istanbul (AFP) - An Istanbul court issued an arrest warrant for US-based Turkish cleric Fethullah Gulen who President Recep Tayyip Erdogan regards as his top enemy, in a controversial case that has strained ties with the EU.The court agreed an earlier request by prosecutors for the arrest notice but it remains to be seen if the United States will show any interest in extraditing him to face trial on terrorism charges in Turkey.The warrant was issued after the court earlier remanded in custody the head of a national TV network and three former police officers -- all of whom are deemed linked to Gulen -- on terrorism charges.Samanyolu TV chief Hidayet Karaca was placed under arrest on charges of forming a terrorist group, after being detained with over two dozen others in weekend raids on journalists, scriptwriters and police accused of plotting to overthrow Erdogan.The court however ordered the release of Ekrem Dumanli, the editor-in-chief of the Zaman daily, which has repeatedly accused Erdogan of running a corrupt regime and who was arrested in the same raids last Sunday.Both the Zaman newspaper and the STV channel are linked to Gulen, a one-time ally of Erdogan whom the Turkish strongman has now vowed to crush without mercy.Dumanli defiantly told hundreds of supporters outside the court after his release that "the press cannot be silenced, media will never succumb to intimidations".Seven other suspects in the case were ordered released by the court in Istanbul while three more -- all ex-police officers -- were also remanded in custody.- 'Forming a terror group' -Erdogan accuses Gulen of running a "parallel state" and being behind sensational corruption allegations against his inner circle that broke on December 17 last year.Gulen, who is believed to have millions of followers in Turkey and runs private crammer schools around the world through his Hizmet (Service) group, has vehemently denied all the allegations against him. Prosecutors asked the court for the warrant to arrest Gulen for leading a "criminal" group acting against the "rules and laws in media, economy and bureaucracy", the state Anatolia news agency reported.According to a copy of the request published in Turkish media, Gulen is charged with setting up and directing an "armed terrorist organisation" as well as using intimidation to deprive a person of their freedom.The court later in the evening issued the warrant, saying Gulen was suspected of creating an "illegal organisation with a hierarchical structure that is separate from the state's own structure", Anatolia reported.The United States has so far paid little attention to repeated requests from Turkey for Gulen's extradition from his secluded compound in the state of Pennsylvania.US State Department spokeswoman Jen Pskai said Washington has seen the reports of the arrest warrant but as a matter of policy it does not "comment on pending extradition requests or confirm or deny that an extradition request has been made".- 'Fictional ruling' -Turkish television said that Karaca had also been charged with "forming and running a terrorist organisation". The three former senior Istanbul police officers arrested -- Tufan Erguder, Ertan Ercikti and Mustafa Kilcaslan -- had been charged with "membership of a terrorist organisation".Dumanli has been slapped with an exit ban from Turkey, indicating he is still set to face trial.