Before Mellors’ release Pearl Black’s brother and sister, George and Mary Black, wrote to the Parole Board to warn them that he would kill again.Ms Black said: “The Parole Board have let us down totally. The justice system has let us down by not listening to us when we warned them this man would commit murder again.”Two good women died by the hands of this monster.”The different agencies should have picked up on this because he had been stalking Janet.” Mellors was released from prison in 2014 and was in a relationship with Mrs Scott while she was temporarily separated from her husband in 2017, and killed her after she got back together with Mr Scott.Mellors stabbed her at her home in Nursery Road, Arnold, Nottinghamshire, on 29 January then drove her towards Nottingham city centre. Simon Mellors killed Janet Scott after his release from prison for the murder of Pearl Black The Ministry of Justice said a full review into the case is under way.A Ministry of Justice spokesperson added: “Serious further offences such as this are very rare, but each one is taken extremely seriously and investigated fully.”A full review into this case is under way, and we will carefully consider the findings to make sure all possible lessons are learnt.”An inquest to examine the circumstances of Mrs Scott’s death has also been opened and adjourned. Simon Mellors killed two women in Nottinghamshire – Pearl Black, 36, in 1999, and Janet Scott, 51, in 2018 A woman killed by a convicted murdered had complained to the probation service fearing for her life, her family have revealed.Janet Scott, 51, was murdered in January after dating convicted killer Simon Mellors, and now her husband Chris Scott has told of how the probation service failed to protect his wife.Simon Mellors, from Nottingham, murdered his former partner Pearl Black in 1999, then killed Mrs Scott after being released from prison on licence.Mr Scott said Mellors threatened to kill them both and followed Mrs Scott to work before she died.”If the probation service had done something and informed the police and had Mellors been arrested my wife would still be alive,” said Mr Scott.Speaking to the BBC he said that his wife knew Mellors was going to kill her. “She knew it was coming,” he said.”I said ‘Look, you’ve got nothing to worry about, I’m here, I’m going to protect you, nothing is going to happen’.” She escaped and ran towards a traffic officer for help, but Mellors drove his car into both of them, injuring the traffic officer and killing Mrs Scott instantly.Mellors died in prison after being charged with her murder and the attempted murder of the traffic officer. He is thought to have killed himself.Mrs Scott’s sister Susan Thomson confirmed that complaints had been made about Mellors to his probation officer. “I knew that my sister sent texts to the probation officer because she rung me up when she did it and told me so,” said Mrs Thomson.”I feel that Simon should have been told, or pulled in, or something done about it, while he was stalking my sister.” Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.