A 58-year-old man was left covered in blood after being headbutted during an unprovoked attack at Santa Pod.
Bedfordshire Police are appealing for witnesses to the attack which took place on Friday sometime between 9.30pm and 10.15pm as the victim and his wife were stood near the front of the live stage listening to a band playing at the Bug Jam event.
A police spokesman said: “The offender, who was also at the front of the crowd, turned and headbutted the victim in the face causing him to fall to the floor.
“The offender then fled leaving the victim covered in blood and in need of medical treatment.”
PC Luke Kennett, who is investigating the attack, is keen to hear from anyone who was at Bug Jam over the weekend and saw the attack.
The offender is a white man, in his late 20s or early 30s and wore a dark hat, blue t-shirt. He had a rucksack on his back.
Anyone with information about the incident is asked to contact PC Kennett, in confidence, on the non-emergency number 101, or text information to 07786 200011.
Information can also be given Crimestoppers anonymously on 0800 555111 or online at crimestoppers-uk.org.