The six Iranians who were arrested for dancing in a YouTube video to Pharrell Williams' song "Happy" have been freed, CNN reports, citing the International Campaign for Human Rights in Iran.

The director of the video was not released, the group said on Wednesday.

According to CNN, one of the six announced that she was freed. "Hi I'm back," Reihane Taravati wrote on her Instagram account, thanking Williams and "everyone who cared about us."

The fan video is one of many to the hit song that has sold millions of downloads worldwide.

Tehran Police Chief Hossein Sajedinia ordered the arrests of the three men and three women for helping make an “obscene video clip that offended the public morals and was released in cyberspace.”

Pharrell Williams denounced the arrests.

"It is beyond sad that these kids were arrested for trying to spread happiness," the Grammy Award winner was quoted as having said on his Facebook page.

Pharrell was not the only one unhappy about the arrests. The Twitter hashtag #FreeHappyIranians went viral, noted CNN, while the National Iranian American Council condemned Iranian authorities.

"There are forces within Iran's government who want to keep the Iranian people isolated from the world," the council said in a statement.

"The irony that the Iranian youth were arrested for dancing to a song called 'Happy' seems to be lost on the Iranian authorities."

Under Iran's Islamic law, women are required to cover themselves from head to toe, though Iranian President Hassan Rouhani has reportedly opposed the Islamic Regime's "morality police".

Iran is also notorious for its internet censorship but Rouhani, who has attempted to show a moderate approach to the world, has indicated that he intends to revise Iran’s censorship policy.

In a speech he delivered a month before being sworn in, Rouhani said that a strong government does not “limit the lives of the people.”

Two weeks after his victory in the elections, Rouhani told a popular Iranian youth magazine that he believed social networking sites such as Facebook were a welcome phenomenon.