Investigations were continuing today after man was electrocuted when a hydraulic crane arm he was operating on the back of a lorry struck an overhead electricity cable at a Hampshire industrial estate.

Witnesses told how the man, aged 26, was thrown almost 10ft by the force of the shock, which happened as he was trying to unload the vehicle at the yard.

Despite frantic efforts by two others working on the estate to save him, the man is understood to have been killed instanty.

Yesterday an electrical expert told the Daily Echo that he thought the power cables could have been carrying up to 11,000 volts.

The accident, at the West Horton Lane Industrial Estate in Fair Oak happened shortly after 11.15am yesterday as the man was trying to offload building supplies from the back of the rented lorry in heavy rain.

One witness, who asked not to be named, said: "It was really nasty. He never stood a chance. By the looks of it the crane arm collided with the cable, which obviously wasn't insulated, and it's sent the charge straight down the arm and into him, throwing him quite a long way from the van."

The Health and Safety Executive was informed about the incident and it is understood that its officers are helping with the inquiry.

Meanwhile electricity provider Southern Electric confirmed that it had shut down power to about 500 properties.