Bekir İrtegün, a 33-year old professional footballer who plays for İstanbul Başakşehir and Turkey national team, have been detained by police over his alleged use of a mobile phone app called ByLock.
Turkish authorities believe using ByLock indicates membership in the Gülen movement, which President Recep Tayyip Erdoğan and the government accuse of masterminding a failed coup attempt on July 15, 2016.
Tens of thousands of civil servants, police officers and businessmen have either been dismissed or arrested for using ByLock since the failed coup attempt last year.
İrtegün initially came to public attention in 2009 when he was transferred to Turkish giant Fenerbahçe on a three-year deal. He later agreed to move to İstanbul Başakşehir in 2015 on a three year contract.