The incident happened as a man was driving his lorry westbound along the A14 in the area of Fen Ditton, Cambridge, at about 3.45pm today (Sunday). The driver suffered head injuries but managed to come to a stop without any other vehicles being affected. Police were called and searches of the area took place, involving the police helicopter, however, no arrests have been made. Detectives are keen to speak to anyone who was in the area at the time and may have dash cam footage. They particularly want to trace anyone who was on a nearby footbridge. Inspector Shane Fasey said: This was despicable behaviour which could have led to a very serious or potentially fatal road collision. Thankfully, other than the lorry driver himself, who was not seriously injured, no one else was injured. It appears to be an isolated incident at this time but we would urge motorists to be cautious around this area of road and report any suspicious activity to police. Anyone with information should call police on 101 quoting incident 271 of today or visit www.cambs.police.uk\/report Alternatively, contact Crimestoppers, anonymously, on 0800 555111 or via www.crimestoppers-uk.org.