Shocking footage has emerged showing a man being brutally beaten with a crowbar as horrified eyewitnesses watch but don't intervene.
The film, recorded on a mobile phone, shows a man cowering on the floor while repeatedly being struck with the metal weapon.
According to Khalid Naeem, who recorded the footage, the attacker had managed to wrestle the crowbar away from the victim and proceeded to beat him with it during the violent confrontation.
The attack took place in the early hours of 26 October on Manchester Street in Luton. The clip of the "nasty, violent" attack has been viewed more than 800,000 times since it was posted onto Facebook.
Bedfordshire Police have now released CCTV images of two men they wish to speak with in connection with the incident.
Bedfordshire Police Detective Con Scott Hannam said: "This was a nasty, violent attack which has left the victim in hospital with serious injuries.
"I am appealing for anyone who witnessed it to contact us, as well as anyone who can help us identify the two men who we believe may have vital information about the incident."
A Bedfordshire Police spokesperson added: "We have issued CCTV images following an incident in Luton on Thursday (26 October) which left a man with serious injuries.
"At around 1:10am a man was in Manchester Street when he was involved in an altercation and assaulted with what is believed to be a crowbar.
"Our officers have now released images of two men they would like to speak to in connection with the incident."
Anyone with information is asked to contact DC Scott Hannam on 101 quoting reference C/46181/2017. You can also call Crimestoppers, anonymously, on 0800 555 111.