Three retired military commanders, who were in charge in 2003-2004 term, testified in Istanbul on Saturday at an in-camera investigation regarding an alleged plot to remove democratically elected party from the government in Turkey.
The military, which has ousted four governments in the past 50 years, had been seen as virtually untouchable and the appearance of high-ranking officers in a civilian court would have been unthinkable only a few years ago.
The officers were released after 9 hours of questioning by prosecutors over what they knew about an alleged military coup to oust the ruling AK Party.
Istanbul Deputy Chief Prosecutor Turan Colakkadi said after the testimony that the commanders were treated as suspects.
Regarding a trial which many in Turkey view as the most significant case of the century, the Ergenekon court case took a new twist last week as prosecutors finally took testimonies of top commanders who were suspected of plotting failed coup attempts between 2003 and 2004 to remove the democratically elected party from the government.
The core argument in the ongoing trial of the "Ergenekon" criminal network was that a clandestine group of people, including members of universities, the media, bureaucrats and the military, allegedly conspired to wreak havoc in the country by masterminding the killings of high-profile people, some of whom were non-Muslim minority leaders. The ultimate aim was the creation of anarchy and chaos ripe for military intervention.
About 200 people, including military officers and politicians are already standing trial over their alleged part in the Ergenekon criminal network.
Turkey is continuing its Accession negotiations to join the European Union and EU officials are closely following the case to see how its democratic institutions stand up to the test.
The military says no one in its ranks had plans to topple the government. The commanders were expected to have responded to testimony given earlier by a former Chief of General Staff, Hilmi Özkök.
While his evidence had been conducted in camera, the former Chief of General Staff later said in newspapers that he had told the prosecutors he had known of the existence of plans to topple the government.
Media outlets have also published alleged excerpts of a diary of former Naval Commander Ozden Ornek from 2004, which referred to the coup.
Ornek was one of the three commanders called to give testimony on Saturday. He served as Naval Commander from 2003 to 2005. Also being questioned were former Land Forces Commander Aytaç Yalman, who served from 2002 to 2004 and former Air Force Commander Ibrahim Firtina who served from 2003 to 2005.
Meanwhile a navy colonel and lieutenant were arrested after being questioned in the same courthouse on Saturday. Their arrests were also under the umbrella of the Ergenekon investigation, but they were implicated in a separate plot, according to police.
Two retired generals have already been arrested in the Ergenekon investigation and are being tried.