Max Clifford's family have claimed he was denied medical treatment after the disgraced PR guru died having collapsed in his prison cell.
The 74 year-old was said to be "in a bad way" after falling twice at the Cambridgeshire jail where he was serving an eight-year sentence for historical sex offences.
The Ministry of Justice confirmed that Clifford, who had been ill since suffering a heart attack in August, died in hospital on Sunday after a cardiac arrest.
Clifford’s daughter Louise, who appeared in court as a witness for her father's defence, has alleged that she had been fighting for medical treatment alongside her father’s legal team and doctor, but without success.
The 46 year-old said: “It is with great sadness that I must announce that my father Max Clifford passed away.
He had been ill for some time with heart problems and myself, his doctor and our legal team had fought for his diagnosis and treatment but to no avail
“He had been ill for some time with heart problems and myself, his doctor and our legal team had fought for his diagnosis and treatment but to no avail.
“He was hugely loved by the many people in his life for the compassionate, kind and funny man that he was."
Clifford's daughter added that she and her legal team, led by Sarah Forshaw QC, will "continue to pursue his appeal hearing and get him the justice he was denied in life”.
On the basis of alleged fresh evidence, Clifford had been due to appeal against all of his convictions early next year. It is not known if the case will be allowed to continue after his death.
Before his death on Sunday morning, the former celebrity publicist was said to be "in a bad way" after collapsing twice at Littlehey Prison.
His daughter told the Mail on Sunday that Clifford first collapsed in his cell on Thursday when he was trying to clean it.
A spokeswoman for Ms Clifford confirmed to the Telegraph that her father cleaned his cell out of choice as he was “conscientious and particular.”
Ms Clifford said he collapsed again the next day and was unconscious for several minutes. After seeing a nurse, he was transferred to a local hospital where he suffered a cardiac arrest on Friday, she said.
Clifford was jailed for eight years in May 2014 after being convicted of a number of charges under Operation Yewtree, the Met Police investigation set up after the Jimmy Savile scandal.
He was the first person to be convicted as part of the national investigation. During his sentencing, he branded his accusers as "fantasists" and was seen laughing and shaking his head in the dock.
The PR guru, who used his celebrity connections to lure women, was found guilty of a string of indecent assaults - with the sex attacks carried out between 1977 and 1984.
In 2016, he was cleared of indecently assaulting a teenage girl, after being accused of using his power to humiliate the 17-year-old into performing a sex act on him in the 1980s.
The former PR mogul crafted a reputation for garnering maximum exposure for the fame-hungry wannabes in his charge.
His previous clients included Muhammad Ali, Frank Sinatra and Chelsea Football Club.
A Ministry of Justice spokesman said: “As with all deaths in custody, there will be an investigation by the independent Prisons and Probation Ombudsman. "Our condolences are with Mr Clifford's family at this difficult time."
When asked about the claim that Mr Clifford was denied medical treatment, a Ministry of Justice spokeswoman said: "All prisoners receive the same level of treatment as anybody would."
NHS England said it was unable to comment on specific cases.