Police officers frisk an employee of the Koza Ipek Group during a raid at the company’s office in Ankara, Turkey, Sept. 1.

Police have detained 11 people in central Turkey, including executives of a conglomerate and university officials, in an operation targeting supporters of a U.S.-based cleric accused by President Tayyip Erdogan of plotting a coup, CNN Turk television said on Wednesday.

CNN Turk said the operation in the central city of Kayseri was aimed at the “parallel structure”, which Erdogan accuses cleric Fethullah Gulen of operating in the judiciary, police, media and business world. Gulen denies the charge.

The detained executives include the chief executive of the unlisted Boydak Holding, active in furniture, energy, and textiles, CNN Turk said.

A Boydak official contacted by Reuters said there was no operation targeting the group and that he was unaware of any detentions. According to its website, the group has annual turnover of more than 6 billion lira ($2 billion) and has more than 13,000 employees.