Two young women and a young man needed hospital treatment after being viciously beaten up in Watford town centre at the weekend.
Hertfordshire Constabulary said the women, aged 18 and 19, and their 19-year-old male friend were near Roosters Chicken, in High Street, at around 4.15am on Sunday when they were approached by two men.
One of the men hit the women in their faces leaving the 18-year-old with a bruised eye and cheek and the 19-year-old a cut to her face and bruised right eye.
The 19-year-old man had his jaw fractured in two places in the attack.
The assailant is described as a black man, aged between 18 and 30.
Detective Constable Garry Madgwick is investigating and said: "This was an unnecessary attack that left the victims with injuries which required hospital treatment.
"I would like to hear from anyone who witnessed the incident and/or the events prior to or after the altercation. Equally, if you believe you know the identity of the offender please contact me straight away."
Anyone with any information in relation to this incident is asked to contact DC Madgwick via Hertfordshire Constabulary’s non-emergency number 101, citing crime reference C1/14/3069.
Alternatively call Crimestoppers, the independent charity, anonymously on 0800 555 111.