A penniless thief murdered a widow who had fostered more than 50 children then tried to destroy the evidence in an explosion, a court has heard.
Gareth Dack used a cable to strangle Norma Bell, 79, stole a boxed TV and £60, and repeatedly used her phone to call sex-chat lines, Teesside Crown Court has heard.
Dack, 33, of Windermere Road, Hartlepool, denies murdering the pensioner at her home in Westbourne Road between April 2 and 3, and a charge of arson.
Christopher Tehrani QC, prosecuting, told the jury Dack tried to cover his tracks with a gas explosion.
He started fires and left the gas hob on in the kitchen. Luckily, the gas did not ignite, he told the court.
Mr Tehrani said: "When he decided to leave the premise one final time, we suggest to you, Gareth Dack decided to cover his tracks by setting fire to the house - for good measure he turned the gas on at the hob - no doubt hoping the gas would ignite and cause an explosion destroying any scientific evidence that he believed he may have left behind.
"Fortunately, the gas did not collect to the point it became combustible."
Outlining the prosecution case on the second day of the trial, Mr Tehrani said: "We suggest you can be sure, when you take account of all the evidence that you will hear, that Gareth Dack is in fact guilty of the brutal and unnecessary murder of Norma Bell and the arson.
"The prosecution suggest Gareth Dack suffocated Norma Bell and killed her.
"He stole the television and sold it for £60. He searched Norma Bell's home looking for money or anything valuable that he could dispose of."
The jury has heard Dack was a drug-user who the week before had asked Mrs Bell, an accomplished book-keeper, to lend him £20.
Mr Tehrani said: "Mr Dack needed cash and he was going to do whatever it took to get the money from Norma Bell."
Dack is accused of attacking Mrs Bell and between midnight and 5am using her phone to call the "soft-porn television service" Babestation as she lay dead or dying on the floor.
He is accused of taking £700 Mrs Bell was looking after for one of her children and police found £405 in the glove box of his car.
The jury has heard that Dack was interviewed seven times by police but chose not to answer all "substantive" questions.
A week after he was charged, he told police he had been "badly advised" to remain silent and claimed his DNA was in the property because he had "done some work for Norma".
The prosecution did not accept that, saying Mrs Bell had a close family who would do jobs for her. Mrs Bell and her late husband John had looked after more than 50 children.
They had three children and six long-term foster children they treated as their own, the jury heard.