A verdict is expected Wednesday against 497 defendants, including former soldiers of the Presidential Guard, who are on trial, accused of involvement in a 2016 failed coup attempt against President Recep Tayyip Erdogan's government.
The massive trial is one of several against suspected members of a network led by U.S.-based cleric Fethullah Gulen, whom Ankara accuses of orchestrating the botched attempt.
Gulen, a former Erdogan ally, rejects the accusation.
The defendants, who have been on trial since 2017, are accused of occupying the headquarters of the state broadcaster TRT in Ankara and of forcing a television anchor to read out a statement on behalf of the coup plotters.
On July 15, 2016, factions within the Turkish military used tanks, warplanes and helicopters in an attempt to overthrow Erdogan.
Fighter jets bombed parliament and other spots in Turkey's capital.
Heeding a call by the president, thousands took to the streets to stop the coup.
A total of 251 people were killed and around 2,200 others were wounded.
Around 35 alleged coup plotters were also killed.
The government has designated Gulen's network a terrorist group, which it has dubbed Fethullahist Terror Organization, or FETO.