Terry Perkins, one of the ringleaders of the £14m Hatton Garden raid, has died in his cell in Belmarsh prison, a week after he was ordered to pay £6.5m in compensation or face a further jail term.

Perkins, 69, a career criminal who had diabetes and heart problems, is understood to have died from natural causes. He was serving a seven-year sentence for the robbery of a safe deposit facility in central London in 2015, during which £14m in jewels, cash and gold was stolen. Arrested a few weeks after the burglary with the other three ringleaders, he pleaded guilty at the first opportunity.

Last week at Woolwich crown court, Perkins was told that he, along with the four others, would have to pay a total of £27.5m or face a further seven-year sentence. The judge, Christopher Kinch QC, said: “A number of these defendants are not only of a certain age but have in some cases serious health problems.

“As a matter of principle and policy it is very difficult to endorse any approach that there is a particular treatment for someone who chooses to go out and commit offences at the advanced stage of their lives that some of these defendants were.”

It emerged during the case that Perkins had to inject himself with insulin during the burglary because of his diabetes. The burglars became known as the “diamond wheezers” because of their poor physical health.

At 35, Perkins had taken part in a raid on the Security Express depot raid in Shoreditch, east London, in 1983. £6m was stolen, the biggest-ever cash robbery at the time.

On the same day, 32 years later, he was part of a team of elderly burglars who broke into the safe deposit centre in Hatton Garden Safe Deposit and initially seemed to have got away with millions of pounds worth of jewels, cash and gold.

Perkins was also facing a fresh charge for a burglary of the jewellers Chatila in Bond Street in 2010. He was scheduled to appear in Southwark crown court for trial last December but was too ill to do so. His co-defendant, Danny Jones, who was also jailed for seven years for the Hatton Garden raid, had already pleaded guilty to the Chatila burglary. He is awaiting sentencing.

Another member of the Hatton Garden team, Brian Reader, is also seriously ill in prison. On Monday, a family member said: “He can’t see properly, he can’t hear, he is vey weak and is down to eight stone.”

Reader, who pulled out of the burglary halfway after the gang had been unable to drill through to the vaults and thus did not receive any of the proceeds, will be appealing against the additional sentence.

Barristers for all of the men ordered to pay or face further jail time have said their clients’ assets do not amount to a fraction of the millions they are being ordered to pay back. John “Kenny” Collins, 77, is the fourth ringleader ordered to pay.

A prison service spokesperson confirmed the death of Perkins, and said: “As with all deaths in custody, there will be an independent investigation by the Prisons and Probation Ombudsman.”