Fellow passengers came to the aid of a woman who was reportedly racially abused on board a bus in Dundee.
The incident is alleged to have taken place on the Xplore Dundee 22 service on Monday, which left the city’s High Street at around 4.45pm.
Police said both the woman and suspect were seated at the rear of the bottom level of the bus.
A force spokesperson said: “The bus was busy, and other passengers intervened to challenge him regarding his behaviour.
“We would particularly like to speak with any of these passengers who may be important witnesses.”
The suspect was described as slim with facial stubble, around 30-years-old and about 5ft 7in.
He was wearing a beige beanie-style hat, a black and yellow Fila hooded top and black bottoms. He also spoke with a local accent.
If you have any information that could help the investigation, call 101 or Crimestoppers anonymously on 0800 555 111.