A NOTORIOUS drugs baron who was at the heart of a North-East heroin empire has died of a suspected heart attack in prison.

John McPartland was jailed for 12 years in March 1998 after he was caught red-handed with heroin worth £375,000.

A Home Office spokesman confirmed the 50-year-old had collapsed and died in his cell at Frankland Prison, Durham, early yesterday.

A post mortem examination last night showed the death to be of natural causes, and Durham Police confirmed there were no suspicious circumstances.

McPartland, of Weatherhead Avenue, Whinney Banks, Middlesbrough, was jailed after he was caught trying to buy what turned out to be of one of North Yorkshire's largest heroin hauls.

He handed over £110,000 at a service station on the A19 near Crathorne in North Yorkshire, for nearly five kilos of heroin brought from the North-West, worth about £375,000 on the street.

At his trial, the judge said that if police and customs had not interrupted the exchange, after trailing the drugs courier from Manchester, McPartland would have "flooded the streets of Teesside" with the Class A drug.

McPartland was linked with crime from the age of 11, when he committed his first offence.

A gangland acquaintance of the dealer said last night: "He was very well known as being a hard man. A lot of people might not be sorry to see him go, except for his family."