A 13-year-old girl was touched inappropriately by a man on the Stagecoach number 10 Tuffley to Cheltenham bus earlier this week.
Officers investigating the offence are urging anyone who was on the bus between 7.30am and 8.15am on Wednesday to come forward.
The girl got onto the bus at Clarence Street in Gloucester and sat on the top floor. While seated she felt someone grab her pony tail and brush their hands along the length of her hair.
She went downstairs and then got off the bus on Shurdington Road at about 8.15pm but the man followed her for some time before turning back.
The man is described as being of mixed heritage, 5ft 6ins tall, of slim to medium build and with short, curly black hair. He had three small rings in one ear and was wearing a plain black jacket and blue jeans.
Anyone with information should call 101, quoting incident is 216 of March 13.
Alternatively information can also be given anonymously on 0800 555 111, or via www.crimestoppers-uk.org. In some cases Crimestoppers offer rewards of up to £1000 where information leads to a conviction.
