Three prisoners who killed a man suspected of child abduction have been sentenced to further jail terms.

Craig Derrick, 31, Brian Laing, 27, and David Till, 33, carried out the attack on Darren Brownlie at Low Moss jail near Bishopbriggs on January 6.

Mr Brownlie, 47, has been remanded in custody as he faced trial for allegedly trying to abduct a six-year-old boy from a car.

He was kicked and punched during a 66-second assault and died of his injuries.

Family have described Mr Brownlie's treatment as “barbaric” as there was a five-hour delay before paramedics reached him, by which time he was “unresponsive” in a pool of his own blood.

The High Court in Glasgow was also told that Mr Brownlie had been accused by other inmates of "ripping them off" by swapping prescription drugs for legal highs.

Derrick, Laing and Till were sentenced after admitting culpable homicide at an earlier hearing.

Laing and Till were each sentenced to six years and nine months. Derrick was handed a six-year term.

The trio had been accused of murdering Mr Brownlie but their guilty pleas to the reduced charge of culpable homicide were accepted at an earlier hearing.

The court had heard how Mr Brownlie died of injuries that included a ruptured spleen and broken ribs.

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Aamer Anwar (above), solicitor on behalf of Mr Brownlie's mother Helen and brother Robert, said the death was "entirely preventable".

He has now written to the Lord Advocate requesting a 'gross negligence' and health and safety investigation into the Scottish Prison Service (SPS), NHS Greater Glasgow and Clyde (NHSGGC) and the Scottish Ambulance Service (SAS).

Mr Brownlie's brother Robert said there was perfect storm of failures by the authorities "which had a duty of care towards him".

Mr Anwar added: "Darren died from internal bleeding caused by a ruptured spleen and he also had broken ribs, all as a result of a cowardly attack by three men.

"No sentence will bring back Darren but there has not been any true accountability for what took place on January 6 this year.

"Darren's mother Helen has been left heartbroken to discover the inhumane and barbaric treatment of her son in his dying hours."

Judge Lord Matthews said: "Plainly this was an attack that was planned with all three of you knowing what was to be done and helping it to be accomplished.

"No sentence I can impose will ever be enough to allay the grief felt by Mr Brownlie’s family and friends. He went into prison to await trial and he and they were entitled to assume that he would be safe there. That proved not to be the case.

The judge said the death would be the subject of a fatal accident inquiry and that Mr Brownlie's family "will undoubtedly have a large amount of questions" into the circumstances and said he hoped "that in due course they will receive answers".

Previously the court heard an ambulance for Mr Brownlie was requested at around 5.30pm but he was not treated by paramedics until for almost five hours.

That hearing was also told Mr Brownlie "would have in all probability" survived if he had been given "timeous" treatment for blood loss prior to being taken to hospital, according to a accident and emergency consultant.

Mr Anwar has also contacted Justice Secretary Humza Yousaf and Health Secretary Jeane Freeman asking them to meet the Brownlie family who were demanding more than just "tokenistic reviews".

He said: "For the SPS or the NHS to avoid any form of responsibility or scrutiny, with reliance on an FAI three to four years down the line is simply not acceptable - such delay puts the lives of other prisoners at risk.

"Darren's family are horrified at the total contempt and lack of compassion shown to them by the SPS who failed to contact them in nearly seven months following his death.

"Nor have Darren's family been contacted to date by the NHSGGC, the Queen Elizabeth University Hospital or the SAS to offer any explanation."

The Scottish Prison Service said Mr Brownlie's death would be subject of a Death in Prison Learning Audit and Review which is the procedure for all deaths in custody.

A spokesman for the Scottish Ambulance Service said: “Due to an ongoing investigation we are unable to comment further.”