Sergeant Omer Halisdemir killed Brigadier General Semih Terzi on the night of July 15, thus breaking the command chain of the plotters.

Some 18 suspects are accused of deliberately killing the soldier, as well as attempting to remove the government of President Recep Tayyip Erdogan.

Acting on his commander's orders, Halisdemir shot Terzi dead outside special forces headquarters in Ankara. He was then himself killed by the plotters.

Hundreds of babies born after the coup have been named Omer Halisdemir as a tribute, while hundreds of thousands have visited his grave.

Parks, schools and other public places have been named after Halisdemir while a cottage industry of souvenirs to preserve his memory has emerged.

The suspects are being tried in Ankara and face multiple life sentences.

Dressed smartly in suits, they were led into the courthouse by paramilitary forces in front of television cameras surrounded by heavy security and a water cannon truck.

The courtroom was packed with security forces including police with shields behind the suspects as the judge confirmed the identities of those on trial.

The coup was blamed on Islamic preacher Fethullah Gulen, living in self-imposed exile in Pennsylvania, and his movement. Gulen strongly denies the charges.

Turkey says the Gulen movement is a terrorist organisation and the suspects in Ankara also face charges of being a member of an armed terror group.

The men went on trial after 47 suspects, mainly soldiers, appeared in court for the first time on Monday in the southern city of Mugla, accused of plotting to assassinate Erdogan.

They are among around 43,000 people arrested in the aftermath of last year's attempted overthrow with the country facing the largest judicial process in its history.