An Istanbul court sentenced a local U.S. consulate employee to jail on Tuesday (October 27) for aiding the network Ankara accuses of attempting a 2016 coup.
Nazmi Mete Canturk, a Turkish security officer at the Istanbul consulate, was given five years and two months jail time.
He was not immediately arrested by the court, meaning that he will be free pending appeal.
His verdict could further strain ties between Turkey and the United States.
Trials of U.S. citizens and consulate workers in Turkey have been among many sources of discord between the two countries.
Canturk is the third U.S. consulate employee to be convicted.
Turkey and U.S. ties have deteriorated over differences in policy in Syria and Ankara's purchase of a Russian missile defense system.
In his final defense on Tuesday, Canturk denied being a follower of the U.S.-based cleric Fethullah Gulen and said his job required coordinating with local officials on security issues.
Gulen was blamed by Turkey for the failed 2016 military coup, in which about 250 people were killed.
Officials say followers of Gulen, a former ally of President Tayyip Erdogan, infiltrated the police, judiciary, military and other institutions.
Turkey considers the network to be a terrorist organization.
Gulen, who has lived in self-imposed exile in Pennsylvania since 1999, has denied any involvement in the coup attempt.