The new arrests follow that of three naval lieutenants late Tuesday evening. Newspapers reported on Thursday that the lieutenants have allegedly received orders for the planned assassinations from two colonels.
Reports claimed that the assassination orders came from two colonels named Tayfun Duman and Orhan Yücel.
Naval lieutenants Sinan Efe Noyan, Faruk Akın and Alperen Erdoğan were arrested on Tuesday. The prosecutors accused the lieutenants of planning assassinations against two admirals, whose first names are Uğur and Metin. At the initial hearing at İstanbul's 11th High Criminal Court, the lieutenants were charged with “being a member of an armed organization,” and they were all sent to prison.
Various Turkish newspapers on Thursday claimed that during a raid, the police discovered a note regarding the assassinations in the quarters of lieutenants Noyan and Akın. “Wait for an order for assassinating Uğur and Metin,” read the note. The note also said the order would come from colonels Yücel and Duman.
According to newspaper reports, the lieutenants were interrogated over their suspected links with the colonels. They denied the charges.
There have also been claims that the lieutenants were in close contact with Maj. Levent Bektaş, who was arrested in April for suspected links with a large cache of ammunition unearthed during excavations on land owned by the İstek Foundation in İstanbul's Poyrazköy district. That discovery had come as part of the investigation into Ergenekon, a clandestine gang whose suspected members currently stand trial on charges of having plotted to overthrow the government.
The military prosecutor's office has also launched an investigation into the claims.
The lieutenants are also accused of being involved in a sex and drug trade operation in order to provide funds to Ergenekon, a clandestine organization accused of planning to overthrow the government.