A prolific drugs baron from Liverpool who has been released from jail after 14 years is now subject to some of the strictest measures ever imposed on a released convict.
In 2013, the island's Royal Court ordered Warren to pay £198 million after he was unable to prove his wealth had been obtained through legitimate means.
He appealed the sentence but lost.
After serving 14 years - with a further 10 years added to his sentence after failing to comply with the £198 million Proceeds of Crime order - he has been released.
But, the 59-year-old, known to some as "Britain's Pablo Escobar", will now face some of the tightest post-release restrictions ever imposed by the National Crime Agency.
Warren will not be allowed to have more than £1,000 in cash, will be banned from using WhatsApp and Facebook Messenger, and will have to give a day's notice if he wants to sit in a friend's car.
He is also said to be banned from holding any cryptocurrency like Bitcoin and to have to give his NCA handler seven days' notice if he wants to travel.
What do the measures imposed include?
Being banned from WhatsApp and Facebook Messenger.
He cannot have more than £1,000 cash on him.
He must give his police handlers a day's notice if he wants to get into a friend's car.
He must give the National Crime Agency seven days notice if he wants to travel outside England and Wales.
For any such travel he would have a provide a very detailed breakdown of where he is staying, how long for, with whom, how he is funding such a trip and his full itinerary.
He is be banned from holding any cryptocurrency like Bitcoin.
Failure to comply with these measures could see him back in prison for up to five years.
The National Crime Agency (NCA) told ITV News action against serious and organised criminals "doesn't end" with a conviction.
"Many serious offenders have had lifelong criminal careers and are likely to reoffend," it said.
"Individuals convicted of serious offences can have additional restrictions imposed upon them enabling us to monitor their activity, manage their behaviour and prevent reoffending.
"These restrictions protect the public but will have little impact upon those who are genuinely reformed."
Warren was born in Toxteth in 1963 and went on to become an international drug trafficker worth tens of millions.
At the time he was believed to have drug-producing contacts in countries including Iran, Morocco, South and Central America, Ghana, Thailand and Australia.
He moved to the Netherlands in the 1990s and was jailed there after police raided his villa and found a huge haul of drugs and weapons.
He was convicted of manslaughter following a prison yard fight with a Turkish inmate.
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