AN INVESTIGATION is under way after a builder was badly injured when he was crushed by three tonnes of steel while working 50ft from the ground at an American airbase.

AN INVESTIGATION is under way after a builder was badly injured when he was crushed by three tonnes of steel while working 50ft from the ground at an American airbase.

A 49-year-old man suffered a fractured pelvis, broken ribs and a head injury after the terrifying incident at RAF Lakenheath on Tuesday morning.

The Health and Safety Executive and the firm hired by the base to build the temporary accommodation block the sub-contractor was working on have both pledged to investigate the accident.

The man, who has not been named, had worked for Cambridge-based J.A. Carr, a specialist structural concrete firm, for a number of years.

Staff have spoken of their shock after he was crushed by three tonnes of steel shuttering while working on the housing unit.

Building company boss Jim Carr said: "We don't yet know how the accident happened but an internal investigation has been launched and we have contacted the Health and Safety Executive.

"We are all a bit shocked about what happened. I have visited the man in hospital, he is in a lot of pain but he is quite coherent and doctors have said there will be no lasting damage."

The builder had to be lowered to the ground by a crane before being airlifted to Addenbrooke's Hospital, Cambridge, by paramedics from the East Anglian Air Ambulance.

The company was sub-contracted by international firm AMEC, which has promised to carry out a full investigation into the accident.

External relations manager Frank Stokes said: "We carry out a lot of work for the Ministry of Defence. We have a good health and safety record and this was a sad but rare accident.

"We will be undertaking an internal investigation to look at why the accident took place and prevent it from happening again."

Mildenhall's community paramedic and an ambulance from Thetford attended the scene along with the base rescue services.

Ministry of Defence press officer Lt Col Stuart Green said: "The 48th Fighter Wing have confirmed an accident did take place at RAF Lakenheath at around 11.40am on Tuesday involving a British contractor.

"The Base First Responders went to the scene and worked alongside British paramedics and ambulance crews."

A spokeswoman for the Health and Safety Executive said: "We have been informed about the incident and we will be investigating. Our next step will be looking at whether we will need to visit the site."