A 70 year old man was left with a fractured hip and cut to the leg after being assaulted.
At around 7pm on Thursday a man was assaulted on the Aylesbury Road near to the Esso Roundabout.
He was taken to hospital for treatment where he remains.
The offender is described as a man of large build, with slicked back blonde/light coloured hair, wearing a hi-vis jacket and shorts.
He was seen to get away in a small white Hyundai car.
Investigating officer, PC Benjamin Green, based at Abingdon police station, said: “I am appealing to anyone who may have witnessed this incident to please come forward.
“Anyone with information can contact police by calling 101 or making a report online, quoting reference 4321046377.
“Alternatively, if you wish to remain anonymous, you can contact the independent charity Crimestoppers on 0800 555 111 or via their website.”