A 13-year-old boy was thrown to the ground in Lavenham last weekend after a man kicked the wheel of the bike he was riding.
The incident occurred when the boy was cycling along a muddy path on an old railway line at the back of Norman Way at around 3.45pm on Sunday, December 3.
The man, who ran away, is described as being in his 40s, of skinny build and wearing beige trousers and a tweed waist-length jacket. He was also walking a small Jack Russell dog.
The boy was uninjured.
Anyone who witnessed the incident or has knowledge of it should contact Sudbury police on 101 quoting crime reference 37/77319/17.