(Bloomberg) -- A Turkish employee of the U.S. consulate in Istanbul went on trial on Tuesday on charges of espionage, terrorism and playing a role in an attempted overthrow of the government in a case that has strained Turkey’s ties with the U.S.

Metin Topuz is facing life in prison if convicted for ties to the outlawed network of Fethullah Gulen, a U.S.-based cleric who is accused by the Turkish government of masterminding the failed coup attempt in 2016. U.S. Embassy Charge d’Affaires Jeffrey Hovenier attended the proceedings.

The trial adds yet another complication to repairing Turkey’s relationship with the U.S. The two NATO allies have been feuding over a number of issues, even after Turkey’s release last year of a long-held American pastor.

Topuz’s arrest in October 2017 already sparked a diplomatic spat with the U.S., prompting Washington to temporarily suspend visa services in Turkey. At the time, Topuz testified that he traveled to the U.S. with members of Turkey’s police, who were involved in a 2013 corruption probe that was allegedly backed by Gulen’s network against Recep Tayyip Erdogan’s government.

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The detention of at least two other people, former NASA scientist Serkan Golge and Hamza Ulucay of the Adana consulate, has also attracted U.S. attention and fueled tensions. Although the U.S. said they’re innocent, they were convicted for ties to the 2016 coup attempt and links to the separatist Kurdish group of PKK, respectively. Ulucay was released earlier this year on time served.

To contact the reporters on this story: Selcan Hacaoglu in Ankara at shacaoglu@bloomberg.net;Baris Balci in Istanbul at bbalci4@bloomberg.net

To contact the editors responsible for this story: Onur Ant at oant@bloomberg.net, Paul Abelsky

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