A prisoner has been detained indefinitely after being convicted of strangling his cellmate with a TV aerial cord – leaving him dead and tucked up in his bunk bed.

Michael Harkin, 35, killed 38-year-old Dan Childs with the cable and also wounded a second prisoner with an improvised blade just hours later.

Bristol Crown Court heard the attacks took place at HMP Bristol in June last year after Harkin had been recalled to prison just 24 hours after being released for breaching his licence.

He strangled Mr Childs as he slept in his bed, then the following morning attacked his former cellmate in the showers.

That prisoner, who had spent just one night sharing with Harkin, had demanded to be moved because “there was something not right” about him.

Staff subsequently decided Mr Childs, originally from Telford, should share that cell with Harkin instead.

Before he died, Mr Childs reported to another inmate that Harkin had threatened to kill him if he fell asleep, telling them: “My cellmate won’t let me sleep, he tells me if I go to sleep he’ll suffocate me.”

The police were called following the attack on the former cellmate and then found Mr Childs dead.

The court heard at the time of the attacks, psychiatrists had concluded Harkin was suffering from schizophrenia and had developed delusions about religion.

Harkin was convicted by a jury of the manslaughter of Mr Childs by diminished responsibility. They cleared him of murder on the direction of the judge.

He was also found guilty of wounding the other prisoner, and not guilty of a separate count of attempting to wound a member of prison staff who sought to intervene.

Mr Justice Bryan imposed a hospital order under Section 37 of the Mental Health Act and a restriction order under Section 41 – meaning Harkin can be detained indefinitely.

“I must now sentence you in the light of the verdicts returned by the jury, set against the backdrop that you remain profoundly mentally unwell, and have been detained in, and remain detained in, Broadmoor Hospital, where it is common ground you will need to remain for treatment for the foreseeable future,” he said.

“Your treating consultant forensic psychiatrist in Broadmoor cannot foresee a time when it would be appropriate or safe for you to be returned to the prison system.”

Describing the attack, the judge said Mr Childs and Harkin were locked into the cell on the evening of June 4.

“At some point you killed him by strangling him with the co-axial cord from the cell TV,” he said.

“It appears from the pathology evidence that you may have strangled him whilst he was asleep as there is no physical evidence of a struggle.

“It appears you then ‘tucked him up’ in his sheets on the top bunk.

“When the cell was opened in the morning you walked out of the cell as if nothing had happened, and CCTV on the landing captures you walking around the landing and interacting with others, no-one being aware that Mr Childs was lying dead in his cell.”

Describing the subsequent attack in the showers, the judge said: “You slashed him repeatedly with the weapon, resulting in deep cuts to his left shoulder and neck, that have resulted in permanent scarring.

“He thought he was going to die, as well he might if others had not intervened, and he had bled out.

“His screams were heard by another prisoner who tried to fend you off with a long-handled mop.”

The judge added: “In terms of why you killed Mr Childs, it appears that Mr Childs had the misfortune to have ‘child’ in his name and this led you to the delusional belief that he was a paedophile, which was completely, and absolutely, untrue and had no basis in fact whatsoever.”