An Ankara court has indicted Turkey's former police intelligence chief, Ramazan Akyurek, as part of the "illegal wiretapping" probe which has seen many high-profile arrests around the country over the past year.
Akyurek was already under arrest for alleged involvement in the murder case of Turkish-Armenian journalist Hrant Dink
The ruling came on Wednesday after prosecutor Alpaslan Karabay referred Akyurek to Ankara's Fifth Peace Court on charges of "forming and managing terrorist organization to commit a crime," and "forgery of official documents."
The Turkish government has vowed to crackdown on the so-called "parallel state" since a graft probe targeted Turkish Cabinet members in December 2013. The current Turkish government claims the move was a coup attempt.
The "parallel state" refers to an alleged group of Turkish bureaucrats and senior officials embedded in the country's institutions, including the judiciary and the police, which is allegedly trying to undermine the Turkish government.
Since the December 2013 graft probes, many police chiefs and thousands of officers have been relocated to different cities, and the top judicial body has been restructured in Turkey.
Government officials have accused the "parallel state" of being made up of followers of US-based Turkish preacher Fethullah Gulen.
The 2013 investigations were based on wiretapped recordings of phone conversations and confidential meetings of government officials.
Later recordings, which were leaked online, included private family conversations of President Recep Tayyip Erdogan, who was then prime minister, and a top-level security meeting attended by Prime Minister Ahmet Davutoglu, who was then foreign minister, and the chief of the military staff, Necdet Ozel.
In late February 2015, Akyurek was put behind bars at Istanbul's Silivri Prison over the murder of Turkish-Armenian journalist Hrant Dink on charges of negligence on the job at the time of the murder.
Dink was one of the founders of the bilingual Turkish-Armenian weekly Agos. He was assassinated outside his office in Istanbul on Jan. 19, 2007.