SCOTTISH gangsters are exploiting the decline of terrorist activity in Northern Ireland to secure a major new supply line for heroin through Belfast.

Ground-breaking new research shows the province’s capital has joined Liverpool and Manchester as a core source of illegal drugs, especially for the lucrative west of Scotland market.

The discovery – revealed through rare interviews with high-level drug dealers by academics – amounts to a significant new headache for law enforcement.

For decades Scotland’s organised crime gangs have largely sourced their drugs through the north-west of England for the final stretch of a supply chain that stretches back as far as the poppy fields of Afghanistan or the coca plantations of South America.

Now – just as police make some headway in disrupting those traditional routes – Northern Ireland, said to be suffering its own post-conflict heroin ‘epidemic’, offers an alternative supply.

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Researchers from the University of the West of Scotland, the University of West London and the Metropolitan State University in Minnesota uncovered the new links as they investigated Scotland’s increasingly globalised drugs distribution network.

The researchers, led by James Densley of Minnesota, wrote “Post the 1998 Good Friday Agreement, the province witnessed a significant rise in drug markets and the consequent emergence of trafficking networks.

“Owing to geographical proximity – coastal Ulster and Scotland are only 12 miles apart – and shared history, the West Coast of Scotland was also supplied from Northern Ireland.”

Mr Densley and his co-authors, including Robert McLean and Ross Deuchar of The University of West of Scotland, said traditional Glasgow crime groups used their Northern Irish and northwest English links to supply much of the rest of Scotland.

They said: “This viewpoint was supported by Police Scotland, who have identified elevated levels of drug supply and disproportionate numbers of drug dealers situated in the West of Scotland.”

Their paper, published by the International Journal of Drug Policy, also detailed other established and alternative routes for drugs in to Scotland, including links to the east coast from Birmingham and organised crime groups often referred to, usually inaccurately, as “Yardies”.

And they also stressed dealers could commute from England and or simply operate online, catering for global tastes now matching global supply.

However, the website of the UK’s National Crime Agency, which studies UK-wide dealing networks, still reports that Scotland and Northern Ireland are supplied from northwest England.

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The Northern Irish drugs market has undergone violent and dramatic change in the last three years. Local sources say eastern European gangs, have moved north from Dublin with both guns and drugs.

At least one recent high-profile death in Belfast involved a new Russian-made Makarov pistol rather than a weapon with a history of use in sectarian or political violence.

Dissident Republican and Loyalist groups - some of which have longstanding connections in to Scotland - have both been linked with drug dealing.

Paramilitaries, however, can also take action against organised criminals. Recent reports suggest a rise in punishment shootings. There has also been a recent spate of heroin deaths in Belfast.

Speaking to The Herald, Mr Densley said “There has been talk of the old paramilitary groups shifting focus somewhat thanks to the different opportunities offered under the new landscape.

“There was always historically a connection to organised crime. If you are sourcing weapons, you are involved in a criminal network. Groups have evolved to do things like drugs to get income.”

Mr Densley stressed the importance of personal connections for the drugs trade and stressed Glasgow-based groups would want to make sure they had more than one supply. He said: “We call that risk mitigation.

“Over the past few years there has been a lot of press coverage around organised crime groups in Scotland that have been taken out of the equation by law enforcement.

“Those groups still operating think ‘do we need to change our strategy so we don’t fall foul of the tactics which got others caught previously?’”.

The new academic paper found direct importation of drugs in to Scotland from outside the UK was less common.

Police sources, citing operational sensitivities, had little to say about the new trade across the North Channel.

Detective Chief Superintendent Tim Mairs, of the Police Service of Northern Ireland, said “Organised criminals, by nature, do not recognise borders and will often seek to identify new routes for movement of illicit goods without detection by law enforcement.

“It is for that reason that the PSNI and Police Scotland, supported by law enforcement partners such as the National Crime Agency, work closely together to identify those groups and individuals and frustrate their activities.”

Chief Superintendent John McKenzie, of Police Scotland, said: “We actively target those individuals involved in Serious and Organised Crime and this includes importation, production and distribution of controlled or illicit drugs. We recognise the harm this causes in our communities.”