A motorcyclist was lucky to escape serious injury after chipboard was thrown from the Coulsdon bypass.

Matthew Field was travelling home to Copthorne, Crawley at about 7.45pm on Friday March 2, when a large piece of chipboard measuring approximately three foot by three foot was thrown over the bypass wall.

The 49-year-old was struck by the wood which landed on his upper arm and chest.

The block sheared off the wing mirror and cracked the bike's fairing causing over £1,000 worth of damage.

He managed to keep the bike upright and move to the side of the road before collapsing on to the pavement.

Mr Field said: "I felt an enormous force fall onto me and just though 'what the hell was that?' I've been to the outpatients department this morning and luckily nothing is broken, I just suffered bruising.

"So many things could have happened and the doctor said if it had caught me round the neck instead of the arm and chest it could have killed me."

Passing motorists came to the financial regulator's aid and police attended the scene.

Mr Field said the culprits deliberately targeted him as there were no other cars around. He hopes speaking about the incident will encourage someone with information to come forward.

He said: "These kids, I assume it was kids, they don't think about the consequences. The combination of the block of wood and the speed of the bike makes it even heavier.

"I just want to say to them don't be so stupid, imagine if it was you and you were struck in that way, how would you feel."

Appealing for witnesses to contact the police Mr Field added: "I've been commuting on that road since 1993, so I will get back on the bike.

"If anyone has any information about who did this, please contact the police, they will do it again if they are not stopped."

Detective Sergeant Steve George from Croydon CID said it was believed two male youths in their mid-teens, had dropped the wood from the footbridge over Farthing Way.

He said: "This was an extremely dangerous incident and could have had extremely serious consequences for the rider.

"We would strongly urge anybody who might have seen the two youths involved in or around the area at that time to contact us and help us with our investigation.

"Anyone with information or who witnessed the incident should call police on 0208 649 0100 or contact Crimestoppers anonymously on 0800 555 111."