Two teens were hit by a man with a metal pole in an unprovoked attack in Brantwood Park on Monday.
The incident occurred at approximately 1pm when three 14-year-old friends were in the park.
Without warning one of the friends was hit over the head by a man armed with a metal pole, causing bruising.
Another of the group tried to help his friend but was also hit causing a small cut to his head.
The offender is described as a black man, approximately 35 years old, with a silver tooth and short black hair which was greying. He wore a grey tracksuit.
The officer in charge of this investigating, Detective Constable Phil Raikes, is keen to trace anyone who witnessed the incident or anyone who can help identify the offender.
DC Raikes said: “It is unclear what motivated the offender to behave in this way as he did not shout any warnings towards the youngsters nor did he make any threats.
“Luckily the victims were not seriously injured and I would urge anyone who can help piece together exactly why this incident happened to contact the police, in confidence.”
Anyone with information relating to this crime can contact DC Raikes, in confidence, at Luton Police Station on 01582 394338, or Bedfordshire Police on 101, or text information to 07786 200011.
Alternatively you can contact the independent crime fighting charity Crimestoppers, anonymously, on 0800 555 111.