Power company bosses fear a tragedy if potentially deadly thefts from electricity sub-stations continue.

Since the summer thieves have been risking electrocution stealing vital equipment, which has caused power cuts affecting thousands of customers.

EDF Energy Networks said the lives of workers sent to repair the damage were also being put at risk.

The power firm is appealing to people to report any suspicious activity to police before someone is killed.

Recent break-ins have taken place in Hove on November 2, Ripe, near Lewes, on November 7, Three Bridges, on November 13, and Ditchling, on November 22.

Power supplies were not affected in these raids, but the thieves were lucky to escape with their lives.

Alan Feakins, EDF's director of customer operations, said: "Despite our appeals in the summer, the situation has not improved.

"We are concerned about the threat to electricity supplies and the risk to public safety.

"As much as we invest in further security for our network we fear it is a matter of time before one of these attacks result in a serious fault on our network, or worse, a death.

"These thieves have displayed persistent disregard for their own lives and placed themselves in situations which dice with death. We are astounded at the lengths they will go to and we will continue to do all we can to stop them."

The company said it could not give details of what equipment has been targeted "for security reasons".

Sub-station defences are now being upgraded in a bid to thwart future raids. EDF also pledged to prosecute anyone caught tampering with its facilities.

Anybody with information is urged to contact 0800 0969960.