Iranian Pharrell Williams fans who appeared in 'Happy' video released by police

It is believed the video's director is still being detained

In this frame grab taken from video posted to YouTube, people dance to Pharrell Williams' hit song "Happy" on a rooftop in Tehran, Iran. (AP Photo)

Six young men and women in Iran have been released by the country’s police, after they were arrested for appearing in a parody video of Pharrell William’s hit song Happy.

The video's director, Sassan Soleimani, was still being detained, according to the New York-based International Campaign for Human Rights in Iran. The organisation also quoted a source close to the family of one of those arrested as saying the group had been told they would be prosecuted.

Since it was uploaded to YouTube on 19 May, the footage has garnered over 300,000 views. It shows three women, not wearing headscarves as required by the country’s law, and three men, lip syncing to the song while they dance on a roof and inside a home in the capital Tehran.

The video, which imitates thousands of similar clips by other Pharrell Williams fans, was accompanied by the description: “We have made this video as Pharrell Williams' fans in 8 hours, with iPhone 5S. “Happy” was an excuse to be happy. We enjoyed every second of making it. Hope it puts a smile on your face.”

Pharrell Williams himself criticised the arrests, tweeting on Tuesday: "It's beyond sad these kids were arrested for trying to spread happiness."

Following her release, one of the dancers, Reihane Taravati wrote on her Instagram account: “Hi, I'm back, thank you @pharrell and everyone who cared about us.” "Love you all so much and missed you so much."

Tehran's police chief, Hossein Sajedinia, said he had ordered the arrest of the six young people featured in the clip because they had created an "obscene video clip that offended the public morals", according to the ISNA news agency.

Earlier on Tuesday, the six young people appeared in a programme broadcast by Iran’s state TV, in which they were described as actors, and apparently expressed their regret at making the video.

"They [the video's makers] had promised us not to publish the video," said one of the women in the footage. She goes on to tell the police the group was tricked into making the Happy video - jarring with the positive message at the end of their YouTube post.

These examples of defiance on social media comes as many liberal Iranians hope President Hassan Rouhani, who has eased the country's antagonistic stance with the West, might also relax the Islamic Republic's social strictures.

In a tweet on Wednesday, Mr Rouhani appeared to express support for the six.

”#Happiness is our people's right. We shouldn't be too hard on behaviors caused by joy,“ he wrote on his English language Twitter account, without specifically referring to the video.

However, Mr Rouhani has delivered few social reforms since his election last year, apparently intent on conserving his political capital for seeking an end to the nuclear dispute, that has involved a politically risky engagement with the United States.

Additional reporting by Reuters