Neighbours called police to the property in Brecon

Concerned neighbours called officers to the property in the Pendre area of Brecon on Sunday evening.

Police and ambulance crews forced their way in and found Margaret Powell, 72, from the Brecon area, and Thomas Morgan, 74, who was from Port Talbot.

The Health and Safety Executive (HSE) has confirmed it will investigate the deaths with Dyfed-Powys Police.

Police said they were treating the deaths as sudden and unexplained.

Neighbours said tests were being carried out on the fire and heating at the house.

A HSE spokeswoman said: "We are assisting the police with their investigation.

"We are awaiting the results of the post-mortems before we decide whether or not to investigate."

Acting chief inspector Andy Twigger said police hoped to know more within the next few hours when the results of the post-mortem examinations should be declared.

"We're keeping a very open mind about that at the moment. The premises are secured and we are awaiting the results of the examination," he said.

"The Health and Safety Executive have already been contacted and we're in liaison with the coroner also."