AN off-road motorcyclist has been left with serious spinal injuries following an accident on Crooksbury Common, Tilford, on Sunday afternoon. A 28-year-old man is currently being treated at the Stoke Mandeville Hospital in Buckinghamshire following the incident, which took place sometime between 2pm and 3pm in an area known as Puckbridge Bottom. He was riding a black and white off-road motorcycle along a bridle track at the time of the collision and no other vehicles were involved. Police are appealing for a female horse rider, seen in the area at the time searching for a horse that had bolted, to come forward as they believe she may have information which could help their investigation. The woman has been described as aged 20-30, of slim build and wearing a riding hat, boots, jacket and jeans. Anyone else who may have witnessed the collision, or has any information which could help police, is being urged to contact Surrey Police's collision investigation unit on 01483 639922.