Four people suspected of making a couple strip naked and forcing them to march on the streets have been arrested in the Tangerang Regency of Indonesia.

The act of 'moral vigilantism' which took place on Saturday (11 November) was recorded and the video went viral.

The unwed couple were accused by locals of performing an unspecified "immoral act" inside a home in a village.

According to Tangerang Regency police chief Sabilul Alif, the couple were pushed into the street by the vigilantes who rebuked them for being "indecent".

"Some were saying, 'let's take selfies. Upload them,'" Sabilul said.

At the beginning of the video, the woman can be seen wearing a T-shirt but the men soon strip her completely naked despite her pleas.

The public humiliation lasted for about an hour and also saw the couple being beaten multiple times, the news website Coconuts reported.

The extent of physical injuries the couple has sustained has not been revealed. They have been assigned psychiatric help to cope with the mental trauma of the abuse, police said.

According to Sabilul, the four male suspects who were caught were directly responsible for humiliating and beating the couple.

Sabilul said public shaming and parading of adulterers is not uncommon in Indonesia but this particular incident sparked outrage after it was revealed that the couple were actually engaged to be married and were not involved in any "immoral acts".

The male victim said he had just brought food for his fiancée when the vigilantes raided her house and the two were forced to admit that they were indulging in intimate acts despite being unmarried.

"He was bringing food, then he went to the bathroom to brush his teeth, and then he was pulled out and forced to admit (indecency) or he'd be stripped naked. But what's clear is that he was initially dressed," Sabilul was quoted as saying by the local news website Detik.

A cyber crimes task force has been formed to catch the person who uploaded the footage of the incident online, the Tangerang Regency police said.

Meanwhile, it was reported that the four suspects could be charged with assault which is punishable by five-and-a-half years in prison or up to nine years if the victims have sustained heavy injuries, the police said.

Earlier in August, a couple who had allegedly committed adultery were paraded through the streets in rural Indonesia. The police charged the man with adultery but no charges were registered against those responsible for the abuse.

In January, two consenting adulterers in Tangerang were forced to march in public, but those responsible were not charged with any crime.