A released killer murdered a woman before dismembering her body with power tools in a bid to avoid going to jail again.Steven Sansom, 45, admitted ­murdering Sarah Mayhew, 38, before chopping her up and disposing of the remains in a river and parkland over a nine-mile radius, the Old ­Bailey heard yesterday.It can now be revealed that Sansom stood in the same court 25 years ago to plead guilty to his first murder after he stabbed a taxi driver in the neck for £25. Then just 19, he was jailed for life in May 1999, serving 20 years before being released on licence in December 2019. The builder was under the supervision of the Probation Service when he attacked Ms Mayhew earlier this year.The victim was last seen alive on the evening of March 7 when she met ­Sansom and went to his home.Police were called on April 2 after a dog in Rowdown Fields in New Addington, Croydon, returned to its owner carrying a human bone. Police later found Ms Mayhew’s head, arms and legs.  Steven Sansom, 45, admitted ­murdering Sarah Mayhew, 38, before chopping her up and disposing of the remains in a river and parkland over a nine-mile radius Sansom was under the supervision of the Probation service when he attacked Ms Mayhew earlier this year Further remains were found nine miles away in the River Wandle on May 21. The victim had suffered bruising to her skull and her head had been shaved. Sansom, who has never provided an explanation for the attack, was arrested four days later.He showed no emotion as he appeared via video link from HMP Belmarsh to plead guilty. Wearing glasses and a grey T-shirt, he admitted perverting the course of justice by dismembering Sarah, disposing of body parts in various locations and cleaning up the crime scene.Prosecutor Joel Smith KC said: ‘On 2 April a gentleman was walking a dog across the field in Croydon. The dog discovered a human bone and the police were called. A pair of arms and legs were found and the head which has been cut up using power tools.’ He said of Sansom: ‘This defendant has a previous conviction for murder to which he pleaded guilty in 1999 and received a minimum term of 20 years.’ In that attack, Sansom pounced on cabbie Terrence Boyle, 59, on Christmas Eve in 1998 after telling friends he wanted £300 to buy Christmas presents, adding: ‘I don’t care how I get the money.’He knifed the popular father of five in the throat and back before running off laughing with £25 he had stolen from him. Mr Boyle managed to stagger into a flat doorway where he bled to death.Described as a gentle and ‘a quiet, unassuming family man’, he had only been working overtime to buy his own family Christmas presents. Police at Rowdown Fields park in Croydon, south London, where Ms  Mayhew’s were discovered by a man walking a dog Police set up a forensic crime scene with tents and taped of areas of woodland as they search an area in southwest London after the limbless torso was found in the River Wandle In April, police were called to Rowdown Fields in New Addington, Croydon, where they discovered Sarah’s arms, legs and head, believed to be sawed off with power toolsCovered in blood, Sansom ran to a friend’s house boasting that he had stabbed him six times and ‘nicked his money’. He later admitted murder, telling the court: ‘I would like to say I realise what I’ve done is wrong.’ Mr Brian Baker KC, defending, said: ‘He cannot explain to this day why a tide of anger came over him. He was short of money and wanted to provide his girlfriend with a Christmas present.’When Sansom was released from jail he posted messages on social media about meeting his daughter and son for the first time, saying: ‘Spoken to my little girl today for the very first time… my baby girl called me “Dad” for the first time. She’s 23.’Within a short time, the builder started posting sexual messages. The court heard that he had been charged with three counts of making indecent images in the days after the murder, but these matters will lay on file.Sansom’s girlfriend Gemma Watts, 49, has also been charged with murdering Ms Mayhew, but is yet to enter a plea.