Former Rear Adm. Namık Alper, FETÖ's so-called "martial law commander" in the southwestern province of Muğla, and former Col. Aytunç Kan were convicted by Muğla's Second Heavy Penal Court for trying to overthrow Turkey's constitutional order through violence as part of the coup bid.
The court said the crime of attempting to overthrow the Constitution includes attempts to overthrow and hinder parliament and the government.
The former officers were charged with attempting to overthrow the constitutional order in Turkey, attempting to destroy the Grand National Assembly of Turkey (TBMM) and halt its operations, as well as attempting to destroy the government of the Republic of Turkey.
Halit Cokan, a prime ministry lawyer, told reporters following the conviction that this is the first time a court has issued a ruling for one of the so-called martial law commanders, who would have been expected to exercise authority if the illegal putsch had succeeded.
FETÖ and its U.S.-based leader Fetullah Gülen orchestrated the defeated coup of July 15, 2016, which left 250 people dead and nearly 2,200 injured.
FETÖ is also accused of being behind a long-running campaign to overthrow the state through the infiltration of Turkish institutions, particularly the military, police and judiciary.