Aberglasslyn man Brendan Allwood, 24, and his employer, 31-year-old Aaron Watt, were using a grinder to cut through a galvanised water pipe under the Buffier Crescent house when they received severe electric shocks about 2pm.

Police believe Mr Allwood may have realised that his employer was in some sort of trouble and tried to pull him free.

"He may have thought that he [Mr Watt] was only stuck or jammed against the pipe and has tried to help him by dragging him free," a police spokesman said.

"Either way, he has touched him and has been electrocuted as a result."

The owner of the house raised the alarm after he saw what happened.

Several neighbours who heard the commotion helped the owner provide first aid for the pair until paramedics arrived a short time later.

Mr Allwood, who had been a promising junior basketballer and had represented the Lower Hunter at a national level as part of the Northern Australia Basketball Challenge, suffered a cardiac arrest.

He was rushed to Maitland Hospital, where he died a short time later.

Mr Watt, a father of two from Rutherford, was airlifted to John Hunter Hospital to be treated for possible internal burns.

He remained in a stable condition last night.

Two WorkCover inspectors from the Strategic Investigations Unit were sent to the Rutherford house last night.

WorkCover said a full investigation was under way.