A lorry driver was knocked unconscious after a cyclist slammed his head in his cab door during a road rage incident.
The trucker told police he had stopped on a narrow lane in Copdock near Ipswich to allow an oncoming car to pass when it happened.
The cyclist rode off and the 48-year-old lorry driver came around and was taken to Ipswich Hospital and treated for concussion.
Police said the cyclist was white, stocky and wearing a white top.
The driver said he had attempted to flag the cyclist down in Elm Lane at about 10:30 GMT to warn him the car was coming in the opposite direction.
He said the cyclist became abusive about the truck being on a narrow lane.
The trucker got out of his cab and said he spoke to the cyclist before returning to his vehicle, but he was then attacked.
When he came to, he started to drive off, but became unwell and was then taken to hospital.
Police said they have spoken to a witness and are keen to hear from the cyclist, who was also wearing sunglasses and white headphones.