ANKARA — Police in Istanbul detained 12 academics, business people and journalists as part of an investigation into an association that was headed by a jailed prominent businessman and activist, Turkey's state-run news agency reported Friday.

Anadolu Agency said professors Betul Tanbay and Turgut Tarhanli of Istanbul's Bosphorus and Bilgi universities and journalist Cigdem Mater were among those detained in simultaneous police operations in the city.

They are being questioned over their links to the Anatolia Culture Association founded by Osman Kavala, a philanthropist businessman who was arrested a year ago pending trial, accused of alleged attempts to "abolish" the constitutional order and the government. No indictment has been issued against him.

Anadolu said police were searching for eight other people linked to the association which says it aims to promote peace and minority rights through culture.

Since an attempted coup in 2016, Turkey's government has been accused of stifling freedom of expression for arresting thousands of people for alleged connections to U.S.-based cleric Fethullah Gulen, whom Turkey blames for the failed attempt, or links to terror groups. It has purged many more people from state institutions and jailed dozens of journalists.