The chief of police in Iran’s West Azerbaijan province says security forces arrested "a large number" of people who danced in a promenade on eve of religiously sensitive date.

The night before 21st of Ramadan is called Laylat al-Qadr (Night of Glory) , which in Islamic belief is when the Quran was first sent from Heaven to the world and also the night when the first verses of the Quran were revealed to prophet Muhammad.

This year 20th of Ramadan coincided with May 13. The reason police made the arrests ten days later was the emergence of social media videos showing the dancing.

According to the Islamic Revolution Guards Corps (IRGC)-linked Tasnim news agency, commander of the West Azerbaijan Police, Massoud Khorramnia, said that his forces arrested the suspects after a video clip of dancing in the city of Orumieh's (Urmia) promenade was circulated on the internet.

The police commander did not say how many people were detained, but said, "some of them are still wanted by the police."

Yesterday, fifteen-second footage of the mass-dancing of the people was published on social networks.

Dancing is public goes against the norms of Iran’s religious government but sometimes during national celebrations, people dance and get away with it. Celebrating sports victories is often one of those occasions.

Orumieh police and prosecutors say the people danced on Laylat al-Qadr, which is "violation of sanctity" and a "violation of the norm."

Laylat al-Qadr coincides with the night before the assassination of Shi'ites' first Imam, Ali ibn Abi Talib, on 21 Ramadan AH 40 (29 January 661).