DETAILS have been officially released on the cause of the fatal electrical explosion at the Enron power station which killed three workers.

Health and Safety Inspectors have completed the first stage of their investigation into the explosion on August 8 at the Teesside site.

The investigation has revealed that during a planned maintenance programme, part of the power station was shut down and the electrical power was redistributed to support the rest of the station.

The voltages in one of the electrical systems was adjusted so a circuit breaker could be closed.

At the time of the shutdown, employees were working to alter the voltage across a large transformer and the two operations at the same time resulted in an explosion and fire. The plant was shut down and did not resume producing electricity until Sunday, August 19.

The next stage of the investigation will consider whether any lessons can be learnt from the accident to prevent it happening again.

One man is still in hospital with serious burns following the explosion.