The family of a man who died in custody has accused the justice secretary of smearing him over claims five prison officers were injured before his death.

Allan Marshall was remanded in custody in HMP Edinburgh when he died of a cardiac arrest while being restrained by several officers on March, 28 2015.

CCTV from inside the prison showed the 30-year-old being dragged from the shower room by prison officers and 43 minutes later he was seen leaving on a stretcher.

Justice secretary Humza Yousaf has told MSPs he plans to ask Her Majesty's Chief Inspector of Prisons to "undertake external assurance" of the Scottish Prison Service's (SPS) review following a fatal accident inquiry (FAI) into the death.

Mr Yousaf and First Minister Nicola Sturgeon are likely to be questioned about the death when Holyrood reopens for business on Tuesday.

In his FAI ruling earlier this month, Sheriff Gordon Liddle stated: "I am satisfied that the evidence which has been led in this inquiry amply demonstrates that Mr Marshall's death was entirely preventable."

On Friday, Mr Yousaf sent a letter to Holyrood's justice committee stating five prison officers required hospital treatment after the incident in Saughton, something which Mr Marshall's aunt, Sharon MacFadyen, believes is a smear against her nephew's name.

The family is upset it took the justice secretary 21 days to respond following the publication of the sheriff's findings.

The 46-year-old, from Rutherglen, Glasgow, said: "It's lies. Why does it take 90 minutes to restrain him with all those prison officers?

"It's unbelievable. I just felt there were no emotions in the letter at all. It's took him 21 days to even respond to it. I just find that shocking.

"It's been heartbreaking. We miss him every day, we talk about him every day.

"I'm actually frightened for anyone else who goes into prison because it could happen to anybody.

"They've found this heart condition and they've blamed it on that rather than saying 'lets look at the CCTV'.

"What we see in the CCTV is horrendous. No one will ever know the truth of what went on in that shower block. He needs to look back at everything."

Sheriff Liddle made 13 recommendations, including ensuring prison officers received proper training while also having the presence of a first responder in any future cases.

A Scottish Government spokesman said: "Our thoughts and condolences remain with the family and friends of Allan Marshall for their loss and none of what is in the letter is intended to minimise the tragedy of Mr Marshall's death.

"The letter confirms that five officers were injured in the incident. Of those, as the Sheriff's determination from the Fatal Accident Inquiry confirms, three officers were injured in the initial struggle. The Scottish Prison Service has also confirmed that two further officers were injured in the incident, one to the back and one to the elbow.

"While Ministers have no role in Crown Office decisions regarding possible prosecutions, nor in the independent FAI determinations of Sheriffs, Mr Yousaf meets regularly with people who have direct experience of Scotland's justice system and would be happy to meet with Mr Marshall's family."

The Marshalls' solicitor, Jelina Berlow-Rahman, added: "I'm quite saddened to see that after 21 days it took Mr Yousaf to respond to the family and once he responded there was no compassion towards the family or understanding that Allan was a family man.

"There was more mention about the officers that were injured."