Mubariz Mansimov Gurbanoğlu, a prominent Turkish-Azeri businessman, was detained by İstanbul police on Sunday as part of an investigation into the Gülen group.

According to the Hürriyet newspaper, the financial crimes unit of the İstanbul police raided Gurbanoglu’s house early in Monday the morning. The police also searched his residence, according to the report.

The Turkish government accuses the Gulen group of staging an attempted coup in July 2016.

The group denies any involvement.