Detectives are hoping a “remorseful” cyclist who witnessed a road-rage attack that left a man in a coma will come forward.
The 52-year-old suffered serious head injuries during an argument with three cyclists in Portland Road, Hove, on Sunday.
One of the trio punched the victim once in the head, which has left him fighting for his life in hospital.
Yesterday, officers were trawling through CCTV images taken from shops near the scene.
They appear to show one of the three male cyclists staying to help after the other two had fled.
Detective Sergeant Julian Deans, from Brighton and Hove CID, appealed for him to come forward.
He said: “One of the cyclists stays to help the victim. It looks like he is feeling remorse about what happened. He then leaves the scene.
“We would urge him to come forward.”
Witnesses are asked to call 0845 6070999 quoting Operation Globe.