Political observer and owner of the MetroPoll polling company Professor Özer Sencar was detained on Saturday.

“Ozer Sencar was taken into custody. We have yet to know the reason for detention. We hope the process to be resolved soon. Respectfully announced to the public on behalf of him. (His family), the pollster’s Twitter account said.

Sencar was, in September, 2016, was briefly detained over his alleged links to the Gulen movement, which the government accuses of masterminding the July 15, 2016 coup attempt.

Sencar is known for his critical views of both the Gülen movement and the government.

MetroPoll is considered one of the few independent survey companies in Turkey.