According to the prosecutor’s office, it's because they're accused of having links to the network of US-based cleric Fethullah Gulen.
Ankara says it was him who orchestrated a 2016 attempted coup.
Those who are facing jailtime include three colonels, eight majors and 10 lieutenants.

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Wildfires spread near Indonesia's new capital, prompting calls for action
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Typhoon Saudel brings torrential rain, flooding to China's coastal areas
US investigates deadly strike on Iranian wedding
India food safety crackdown targets company of Nepal's 'Noodle King'
Nepal flood losses estimated at $2.56 billion, official says
