Kozinoğlu died on Nov. 12, 2011, due to an alleged heart attack at the Silivri prison complex, located on the outskirts of İstanbul.
He had been arrested as part of an investigation into the Odatv news portal, which is accused of aiding and abetting Ergenekon, an organization that allegedly plotted to overthrow the elected government. He was the sole MİT official arrested as part of the Ergenekon probe and has been described as the Special Forces Command and MİT's “black box.”
His death raised suspicions about whether he was killed, as he was scheduled to appear in court on Nov. 22.
The Ministry of Justice made a statement concerning Kozinoğlu's death on Nov. 13, saying the initial autopsy on his body showed no evidence of assault. The ministry noted he felt faint after doing heavy exercise, citing the testimony of his cellmate.
However, his family refused to link Kozinoğlu's death with exercise and raised the possibility of murder, arguing the former MİT official had played sports throughout his life.
Initial tests conducted by the ATK showed there was a blockage in his arteries but it was not serious enough to lead to a heart attack. Tests also revealed that no blood clot blocked his arteries and there was no sign of bionecrosis -- physiological death of cells and tissues -- of the heart, which is one of the most widespread cause of heart attacks.
Health experts say heart attacks occur in patients whose heart tissues die as a result of not receiving sufficient oxygen.
Forensic experts are now examining the prospects of whether Kozinoğlu's death might have been triggered by sudden arrhythmia. However, the fact that Kozinoğlu had no pre-existing health problems weakens this possibility because the symptoms of arrhythmia were likely to have been observed many times before his death.
According to claims, Kozinoğlu suffered sudden arrhythmia after being given a toxic injection.
The ATK is now carrying out the second phase of examinations on tissue samples from Kozinoğlu's body and checking blood samples for traces of more than 100 poisons.
When Kozinoğlu's death was linked to a heart attack caused by heavy exercise, his son Özel rejected these claims, saying, “My father did not have a heart problem.” His daughter, Fügen Bıçakçıoğlu, added: “My father played sports from an early age. He won world titles in various disciplines. It is not credible to claim that a person who was so active died due to exercising in jail.”
A Turkish daily claimed last year that Kozinoğlu kept MİT Undersecretary Hakan Fidan and his family under surveillance and shared this information with the owner of Odatv, Soner Yalçın. Yalçın is currently under arrest on charges of membership of a terrorist group and stealing and publishing confidential state documents.
In addition, Kozinoğlu allegedly had close relations with Alaattin Çakıcı, arguably the most infamous mafia boss in Turkey. He is known to have had several phone conversations with Çakıcı in the past while trying to help the mafia boss flee Turkey. In an earlier testimony to prosecutors, Kozinoğlu said MİT learned about the planned assassination of a senior politician in Turkey and that he was trying to prevent it by maintaining close contact with Çakıcı. It was later suggested that the politician in question was former Prime Minister Mesut Yılmaz.