A passenger suffered fatal injuries when a bus driver was forced to perform an emergency stop, an inquest heard today.
Barbara McCracken, 88, was thrown forward when the driver slammed on the brakes after a motorist allegedly cut him up.
The great-grandmother suffered a broken neck and died in hospital two days later following the close shave in May last year.
The motorist - a blonde woman in her 30s - has never been traced and may be unaware that the near miss had such tragic consequences.
Avon Coroner's Court was told that Mrs McCracken, from Stoke Gifford in Bristol, was a passenger on the No 18 First Bus service on the morning of May 16.
The near collision happened on Southmead Road in Filton as the single decker bus - travelling at around 25mph - passed through green traffic lights.
Bus driver Raymond Payne told the hearing that out of nowhere a gold-coloured hatchback car crossed his path - forcing him to brake suddenly.
"I suddenly noticed a car coming across my path from the right side," he said in a written statement read to the court.
"I realised I had to brake as otherwise there would be a collision. The car also braked and stopped right in front of me.
"We looked at each other and I saw the shocked expression and said 'what are you doing?'
"The lady look at me mouthed something at me, I didn't say anything or mouth any words back to the lady."
Passenger Briony Daniels was sat at the back of the bus and saw Mrs McCracken thrown forward by the force of the emergency stop.
"The lights changed to green and the bus proceeded. I would estimate the driver was travelling at 25mph," she said in a statement.
"The elderly lady was thrown forward out of her seat and she reached out to grab hold of something.
"I heard the sound of a thud."
Miss Daniels, who rushed forward to help the stricken widow, said she saw the car driver.
"Her facial expression was angry and she was mouthing something at the bus driver but I could not hear what she said," she said.
"From the expression on her face I would say she was swearing at him and I did not hear the bus driver say anything in response.
"I would say that the lady thought she had right of way."
Miss Daniels phoned 999 and both she and Mr Payne tried to help Mrs McCracken until paramedics arrived.
The retired civil servant was taken to Frenchay Hospital but died two days later. A post mortem examination found Mrs McCracken had died from a fracture of her spinal cord.
Despite extensive police inquiries the female driver has never been located.
Had police been able to trace the woman a file would have been passed to the Crown Prosecution Service to consider pressing charges, the hearing heard.
Deputy Avon Coroner Gail Elliman recorded an accidental verdict.
She added: "I think from what we heard the woman that was driving never knew."
Speaking after the inquest, Mrs McCracken's son Brian, 64, said he hoped that the driver of the car did not know what had happened.
"We would be even more upset if she did know," Mr McCracken, who was with his wife Christine, said.
"The police have been absolutely superb and I don't think they could have done any more."