Published: 11:00, 09 February 2017
| Updated: 12:10, 09 February 2017
Police want people who filmed an unprovoked gang attack - which left the victim with a fractured skull - to come forward.
Officers say at least two people may have filmed or photographed the incident in Tonbridge High Street on mobile phones.
The 21-year-old victim was reportedly punched in the head during a row involving up to 20 people.
It happened opposite Tonbridge Castle, between 11pm and 11.20pm on Christmas Eve, but details have only just been released.
Police say they have made extensive enquiries following the assault, including reviewing CCTV and speaking to potential witnesses.
Three people have so far been arrested in connection with the incident. All remain on bail until April 24.
PC Stuart Shields said: "This is a complex investigation and we have already spoken to a large number of people who were at the scene when this incident occurred.
"We believe the victim was simply minding his own business when, whilst a disturbance was going on nearby, he was approached by someone and punched in the head.
"It appears he then struck his head on the floor as he fell to the ground. The victim suffered some very serious injuries, which could still have long term consequences to his health."
If you can help, call the west Kent appeals line on 01622 604100, quoting reference YY/29179/16, or Crimestoppers, anonymously, on 0800 555111.
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