(CNN) Authorities in Iran arrested 30 people as they took part in a private yoga class in Gorgan, a city in the north of the country, according to an official news agency, the Young Journalists Club.

The men and women in the class were participating while wearing inappropriate clothes, the Young Journalists Club said.

The Young Journalists Club quoted a member of the Crime Prevention Unit in the Golestan Province judiciary as saying that the yoga teacher was among those arrested, and that his case had been referred to the the prosecutor's office.

The Tasnim news agency also reported on the case.

The Crime Prevention Unit official said the man teaching the yoga class had advertised it on social media, according to the Young Journalists Club, and that he did not have a license to teach.