The McKay family has been offered compensation

Denise McKay told BBC Scotland that she thought the house had been targeted by thieves when she found items had been taken out of a cupboard and moved around the kitchen.

Consumer body Energywatch described the case as the worst it had ever come across.

Scottish Gas has apologised for its actions and offered to compensate the family with �250.

Set up accounts

Andy McKay initially decided to switch suppliers after a Scottish Gas salesman visited the house in Livingston.

However, he had a change of heart and tried to cancel the move within days - although the message did not seem to get through.

Scottish Gas set up gas and electricity accounts for him, even though his electricity was still being supplied by Npower.

Mr McKay told BBC Scotland that after a number of attempts to resolve the situation he thought he had sorted things out.

I immediately knew that someone had been in the house, so my automatic thought was that we had been burgled Denise McKay

"After that I thought I finally got through to them and it was cancelled," he said.

"I took the contract and just threw it in the bin because I thought that was it.

"In hindsight that wasn't the wisest of moves, but what is the point in having folk in call centres if you can't do business over the phone."

However, he continued to receive letters and bills from Scottish Gas.

Mr McKay said he ignored them because the company was not listening to him.

Moved around

Scottish Gas then obtained a warrant and broke into his home to install a prepayment meter.

Mrs McKay said she arrived home to find that things had been taken out of the cupboard containing the meter and left in the hallway.

"I looked through into the kitchen and things had been moved around," she said.

"I immediately knew that someone had been in the house, so my automatic thought was that we had been burgled."

Wrong information

Energywatch described the incident as "disgraceful".

The watchdog said there should be further investigations into how a warrant was issued on the basis of wrong information.

Scottish Gas said it was "extremely sorry" and was working hard to remedy the situation.