A bus driver was knocked unconscious by a man in Norwich after confronting two others who stepped in front of his bus.
Police are appealing for witnesses to the assault in the city on the afternoon of Monday, April 1.
It happened at about 4.30pm, when two men stepped in front of the 44A Sanders Coaches bus, which was travelling from Anglia Square onto Edward Street.
The bus driver, a man aged in his 50s, swerved to avoid the men before getting off the bus to speak to them. The driver was then been approached by a third man who punched him in the face, knocking him unconscious.
As a result of the incident the victim was taken to hospital, where he remains for treatment.
Charles Sanders, director of the Holt-based firm, said the driver had suffered a head injury and that the company's main concern was his welfare.
'Clearly we are appalled that a driver has been injured in such a way as he was doing his job,' he said. 'All his colleagues and friends here wish him a speedy recovery.'
He said drivers had experienced problems in the past with customers shouting or becoming angry, but they had never seen an incident of this severity.
A waitress in a café which backs onto the road said she could hear shouting while working in the kitchen on Monday afternoon.
And a café manager down Magdalen Street added: 'Because of where the café is we were not able to look out at the incident, but when my daughter came in from school about 4.30pm she said she could see a crowd of people and a police car, but didn't know what had happened.'
On Twitter, Sanders Coaches tweeted on Monday night to say the bus would not be running due to a 'serious incident', apologising for inconvenience and saying the matter was 'out of our hands'.
Norwich Park and Ride also tweeted to say its buses were diverting at the time, and sent their 'best wishes to the Sanders driver involved'.
Officers are keen to speak to any witnesses or anyone who has any information concerning the incident. They are asked to contact DS Mick Roxby at Norwich CID on 101 quoting reference 36/21858/19.
Alternatively they can contact Crimestoppers anonymously on 0800 555 111.
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