Turkish police on Wednesday arrested 11 people, including a senior business leader, as part of a crackdown on followers of an influential US-based cleric accused of plotting against President Recep Tayyip Erdogan, local media reported.
The arrests took place in the central city of Kayseri, where police raided a university that has been linked to Fethullah Gulen, Dogan press agency reported.
Memduh Boydak, head of Boydak Holding, a conglomerate with interests in real estate, furniture and the energy sector, was among those detained, along with several other business people and academics, the agency said.
The investigation is looking into complaints over the way in which the foundation of Kayseri's private Meliksah University acquired land next to the campus.
Boydak is chairman of the foundation's board of trustees.
Wednesday's raids was the latest in a series of swoops on businesses and media carried out under the auspices of a "terrorist investigation" into Pennsylvania-based Gulen's powerful Hizmet (Service) movement.
Erdogan accuses his former ally of trying to topple him by directing his followers in the Turkish administration to launch a vast probe into government corruption in 2013, which led to the resignation of four ministers.
Gulen, who left for the United States in 1999 to escape charges of anti-secular activities by Turkey's then government, denies the allegations.
Erdogan survived the corruption scandal but has had Gulen and his followers in his sights ever since.
The police and judiciary have been purged of thousands of alleged pro-Gulenist elements and several people considered close to the cleric have been arrested.
Earlier this month, police raided the offices of the Koza-Ipek Media group, which is critical of the president and close to Gulen.
Turkey's main industry federation Tusiad, of which Boydak is a board member, expressed "concern" in a statement Wednesday over his arrest, saying the allegations against the businessman created a "disturbing" climate in which to conduct business.