An Exmouth mental patient stabbed a woman to death in a country park just hours after warning police that he would kill a stranger unless he was admitted to hospital.

Cameron Davis killed 74-year-old Lorna England as she walked across Ludwell Valley Park in Exeter on the afternoon of Saturday, February 18 last year.

 He cut her throat and stabbed her through the heart with a kitchen knife, which he had bought within minutes of being released from a mental health assessment at the Royal Devon and Exeter Hospital.

 He had been taken there by police after he threatened to set fire to his supported accommodation in Exmouth during the early hours of the morning.

He told health professionals that he would carry out a random killing if he was discharged from hospital, but was warned that it would be seen as a pre-meditated attack if he did so.

Davis responded by saying the police could never pin anything on him, Exeter Crown Court was told.

 He blamed the police and hospital for releasing him when he was arrested, saying: “I warned you. Why didn’t they listen to me at hospital? The people at hospital should pay for this. I cried out for help.”

Davis, aged 31, of Exeter Road, Exmouth, denies murder but the jury have been told he has admitted manslaughter by reason of diminished responsibility, a plea which has not been accepted by the prosecution.

 Miss Jo Martin, KC, prosecuting, said Mrs England left home to walk to Lidl to buy flour on the afternoon of February 18, leaving her husband David, who she had been married to for 52 years, waiting for her at home.

 She was killed on a path in woodland by Davis, who had been wandering around at the back of the Wonford Sports Centre for more than half an hour while drinking vodka. She had a non-fatal wound to her neck, a fatal wound to her chest and defence wounds on her hands.

 The attack was witnessed by a dog walker who at first thought she saw two people dancing but then realised it was one blocking the other’s path. She heard Mrs England cry out and fall to the ground.

 Davis took her phone and told the witness in a matter-of-fact way that the injured woman had suffered a fit and she needed to call an ambulance. He dropped the knife in a brook and discarded the phone and a hoodie as he walked out of the park onto Hazel Road.

Miss Martin said Davis had been given notice to quit his accommodation in Exmouth two days earlier and called police at 4.41 am to say he was about to set fire to his room and had taken 30 Valium tablets.

He told officers and ambulance crew he would commit a crime if he was not detained.

Miss Martin said: “He said he was going to kill someone if he was released that day. He said he had committed crimes in the past and always got away with it. He repeated that if he was discharged he would kill a random person.”

She said he was taken to the RD&E for assessment but eventually discharged late in the morning, after threatening once again to kill someone.

 Miss Martin said: “He was told that if he did anything, it would be premeditated. His response was that police could never pin anything on him.”

 She told the jury that a forensic psychiatrist called by the prosecution would tell them that Davis was not so seriously ill that his responsibility was diminished.

 She said: “His view is that he had a personality disorder rather than a mental illness and that personality disorder, combined with drug and alcohol abuse, led to him being a manipulative and angry man.”

The trial continues.