Police want to trace a man thought to have filmed an attack near an Edinburgh museum which left the victim with serious head injuries.

The incident took place at about 2am on Sunday at the junction of George IV Bridge and Chambers Street, near the National Museum of Scotland.

A 21-year-old man was taken to Edinburgh Royal Infirmary having been left with a serious head injury after being attacked.

Officers are trying to trace a group of four men, who were last seen walking north on George IV Bridge, as part of the investigation.

One passer-by is believed to have filmed or photographed the incident on their phone.

Detective Constable Iain Wallace, of Gayfield CID, said: "We're currently working to establish the full circumstances surrounding this assault and are eager to trace anyone who may have witnessed this.

"We believe that a passer-by may have video footage or images of the attack on his mobile phone and would urge this person to get in touch with us as soon as possible to help with our enquiries."

Those with information have been urged to contact Police Scotland on 101, quoting incident number 0607 of December 3, or report anonymously via Crimestoppers on 0800 555 111.