The 23-year-old victim was asked for a light by the girl around 9.30pm on Tuesday last week.

After replying that he didn’t smoke, she spat in his face several times, and began shouting abuse.

As he cycled off, two men then pulled up in a red car. One got out and accused the victim of assaulting the girl, before hitting him several times on the arm. He threatened to burn him with a cigarette, and then got back in the car and drove away – watched by another motorist.

PC Helen Castle, of Newbury police, said: “This was a very distressing incident for the victim and we really need help from the public in tracking down those involved.

“The over-reaction from the offenders is worrying and I need to speak with them. The victim remembers another motorist witnessing the second part of this incident and I would like to hear from that person and anyone who thinks they may know who is responsible.”

The woman is white, aged 17-18, with short brown hair and wearing a big white jacket.

Anyone with information is urged to contact PC Castle on 0845 8 505 505 or crimestoppers on 0800 555 111.