CHILLING police videos have revealed how the callous daughter and grandson of an 84-year-old woman repeatedly denied her murder.

Grandson Barry Rogers was arrested after an ex-partner told police he had confessed to killing frail Betty Guy at her home in Johnston near Haverfordwest in Pembrokeshire.

Police arrested his mother, Penelope John, from St Dogmaels, when they realised that she had lied about Betty’s medical condition in a call to emergency services the night that Betty died.

Now police tapes, to be broadcast on ITV Wales’ Crime Files at 8pm on Monday night, will show how those lies continued as the mother and son were interviewed by police officers.

Rogers, a 33-year-old ex-soldier from Cardigan, told how he drove, “pretty fast”, from his then home in Frome, Somerset to his grandmother’s home in Pembrokeshire. But he insisted: “By the time I got there, my nan had already died.

“My nan died of old age, just old age”, he told officers.

“She was 84. She wasn’t a spring chicken anymore.”

His account was challenged by an officer during an interview.

“Is it a case that you saw your nan was in so much pain that you took it upon yourself to end her life, to end her misery?”, she asked.

“No, no,” replied Rogers.

“Did you use a pillow to cover her face”, the officer continued.

“No.”

“Did you use a cushion to cover her face?”

“No,” replied Rogers, calmly, his arms folded across his chest, but his legs twitching rapidly.

In another police interview in the programme, John is seen insisting: “My mum passed away on her own.”

But police had put secret recording devices in her St Dogmaels home and had heard her son confessing: “I did it.”

Penelope John was challenged about the admission but said: “I didn’t hear that.”

She was again challenged by officers: “In relation to Barry’s comment: ‘no honestly, you’ve got nothing to worry about, it’s me the one that’s done the act’, what did Barry mean by this?”

“I don’t know but my mum died by herself and I was in the bedroom”, John replied.

Tearfully, she insisted: “She was everything to me. Everything. And all this is horrible.”

The interview video also shows Rogers being asked if he was aware that police had bugged his mother’s house.

He insisted he was, because, he claimed, he bought a bug detector on eBay after being arrested and released from custody.

He told officers: “Everything I said was to take the p*** out of you pigs”.

“Why did you feel the need to do that, then,” he was asked?

“Because it was a f*** joke, mate”, he replied.

When challenged on how he’d managed to buy the device during his journey home in a police car, he decided to stop talking.

A police officer asked: “I’m aware of Amazon Prime, whereby deliveries can get turned around within a couple of days. Was it from a local buyer on eBay?”

“No comment.”

“Was it through some sort of Prime shipping service?”

“No comment.”

“You’ve just left the police station, you’ve denied everything. You’re claiming to be the doting grandson. Then you get through the door and within minutes, you’re saying ‘but I did it.’”

“Can you help me understand, or even explain to the jury listening to this, why you’d say such a thing?”

John and Rogers both pleaded not guilty to murder at Swansea Crown Court and under cross-examination denied everything.

They were each given a life sentence in February 2018, with a minimum of 11 years in jail. Both went on to appeal their sentence but lost the appeals.

Crime Files will be broadcast on ITV Wales at 8pm on Monday, September 17