Police in Portugal have confirmed they have launched an investigation after being tipped off about an extraordinary video of a couple having sex next to a child.

A video of the mystery brunette riding a bare-chested man in broad daylight in a park by the youngster as other families played nearby, has gone viral.

Stunned onlookers filmed the shocking scenes at the river beach of Tabuao near the town of Paredes de Coura in the Porto region of northern Portugal.

The woman, who protected her modesty with a sarong, can be seen looking at the men filming her and smiling during the amazing 11-minute footage.

Police confirmed today they were trying to discover the identity of the couple.

A source said they had been alerted by a local who saw the footage on the Internet.

He said: 'Once it had been discovered that the video that was the subject of the complaint existed, police in Paredes de Coura alerted Policia Judiciaria officers to inform them a minor appeared in a sex video which had been posted on the Internet.'

It is understood a specialist PJ unit has been given the task of identifying the couple involved.

The brunette makes no attempt to hide her identify in the X-rated footage - and at one point even talks to the girl beside her while she is bouncing up and down on her partner.

Disgusted social media users called for the pair to be punished.

Elvira Nogueira said: 'They're not worthy of being parents. They should protect this youngster from intimate acts like this.'

Susana Pereira added: 'What I'm seeing in this footage is perverse.

(Daily Mail)