A man working at the site of Trowbridge Rugby Club's new ground was electrocuted after an industrial crane came into contact with power cables this morning.
The man, in his 30s, was standing near the crane when it touched the wires at about 9am, at the site, in Devizes Road.
The man, treated initially by paramedics, was transported to the Royal United Hospital in Bath, by air ambulance at 9.45am.
The man, employed as a banksman, is believed to have been electrocuted and was in cardiac arrest, with medical staff using a defibrillator to resuscitate him before he was taken away from the scene.
It is understood the man was alongside the crane guiding it.
The crane was moving steel beams into place as part of work to build the new clubhouse. Work at the site has now been halted.
Sgt Pete Tuite said: "All I can say at the moment is that there has been an industrial accident."
The site is being run by Ashford Homes.
Police and workers from Southern Electric are at the scene. Power supplies are understood not to have been affected.
The Health and Safety Executive has been alerted.