YANGON (AFP) - Myanmar police said they had launched a criminal investigation into what was described as the first high-definition (HD) pornographic movie ever filmed in the socially conservative country.

Social media exploded this week when a trailer for the two-hour erotic movie, entitled The Violet Of Myanmar, was posted on Facebook by the production company Art Of Myanmar.

The company said on Monday (April 24) that it was proud to have launched the country's "first ever HD" pornographic film and promised to bring more hardcore action soon.

The actress in The Violet Of Myanmar wears a surgical mask and has her face blurred throughout the film.

Art Of Myanmar said it had cost them 400,000 kyat (S$406) to make the film, which was inspired by the protagonist's bright purple traditional skirt.

They said their Viber account crashed after they received more than 2,000 messages in 24 hours from eager customers.

But the firm's Facebook page was taken down two days later and police said they had opened an investigation into the production company.

"Myanmar police are now in the process of investigating to take action, especially the crime department," the head of the police force's Communication and Technology Department, Colonel Tun Nay Win, told AFP.

He added that "the case is concerned with technology" but declined to give further details on what laws the company may have violated.

Owning "obscene" material is illegal in Buddhist-majority Myanmar, where many people are deeply religious, and talking about sex is often considered taboo.

Internet access has expanded hugely since the military junta that ran the country for 50 years handed over power in 2011.