Iranian media reported that police arrested a number of teenage girls for removing the obligatory veil during a sports gathering in the southern city of Shiraz, in addition to some of the event's organizers.

The official "IRNA" news agency, quoting Shiraz Police Chief Faraj Shojaei, reported that a number of girls took off their headscarves at the end of the sporting event, without regard to religious considerations and legal rules.

"In coordination with the judicial authority, a number of perpetrators and those responsible for this gathering were identified and arrested on Thursday," Shojaei said.

A video clip of the event, organized under the title "Skateboarding Day," went viral on social media on Tuesday.

Shojaei added that "organizing any mixed sports or non-sports gathering without taking into account religious or legal norms is prohibited (...) and the organizers will be dealt with according to the law."

IRNA quoted Lotfullah Shaibani, mayor of Shiraz, as saying that the occasion "was held with the intention of violating social, religious and national rules and norms."

Iran requires women to wear a headscarf that covers the hair and neck under Islamic law, in force since the 1979 Islamic revolution.

However, during the past two decades, many Iranian women have allowed their headscarves to slide back to reveal more head hair, especially in Tehran and other major cities.

Sunday, Iranian media reported that police had arrested 120 people over allegations of "criminal acts" including drinking alcohol, mixed dancing and removing headscarves during a party in a forest in the north of the country.

Under Iranian law, only non-Muslims are allowed to drink alcohol for religious purposes. Dancing with the opposite sex is prohibited.