New Delhi, Dec. 26 -- The president of Fenerbahce, one of Turkey's leading sports clubs, was taken into custody in Istanbul on Wednesday as part of a widening drug investigation that has ensnared prominent entertainment and media figures, state media reported.

Sadettin Saran, a dual citizen of Turkey and the U.S., was detained just hours after forensic tests detected traces of narcotics in his hair samples, according to state broadcaster TRT.

He had been summoned last week to testify before prosecutors and was sent to a forensic medical facility to provide hair and blood samples.

Since early December, more than a dozen people have been taken into custody as part of an investigation overseen by the Istanbul Chief Prosecutor's Office.

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