Three men carried out an unprovoked attack on a man who was walking.
The incident happened at 10am on Monday at Leslie Road in Glenrothes.
Fife Constabulary said the men had got out of a white "pick-up" style van with blue poles on the back.
At the time the victim of the assault had been walking towards the Leslie roundabout.
The men, who were described as wearing 'work' clothes and high visibility vests, assaulted the man before driving away towards Leslie. The registration number of the van may have started with 'SL51' or 'SL61' or similar.
PC Sarah Thomson, who is leading the inquiry, said: "This was an unprovoked assault by three men on a lone man. Fortunately the man made good his escape before he sustained serious injury, however the consequences could easily have been more serious.”
She added that it had been raining heavily at the time of the assault.
Anyone with any information is asked to contact Fife Constabulary on 0845 600 5702 or Crimestoppers on 0800 555 111.