Dissident republican terrorists claim to have more than a tonne of Semtex explosive

Members of IRA splinter groups say the explosives could be used in attacks on the British mainland

Dissident republican terrorists are boasting they have more than a tonne of Semtex plastic explosive that escaped the decommissioning process and could now be used against mainland targets.

Provisional IRA veterans who disagreed with the peace process, and who have expertise in handling Semtex, are among those who have access to the secret weapons dumps.

They claim to have tested it and confirmed it is still viable, even though it was smuggled to Ireland via Libya in the 1980s.

Recent raids by police in Northern Ireland have turned up small quantities of Semtex, but a source has told the Telegraph that purpose-built bunkers dotted across the island contain up to 1.5 tonnes of it.

The source said: “It is in the hands of people who will use it, who know how to use it and have used it in the past.

“It has been tested and modern detonators and modifications made, using modern technology, with work going on to counter-act any blocking signals by the security forces.”

The source said dissidents were planning a new campaign against the security forces in Ulster before turning their attention to high value targets in mainland Britain.

There are also fears that the explosives could fall into the hands of criminal gangs who showed their ruthlessness with two tit-for-tat murders in Dublin this month, using guns thought to be former IRA weapons.

Police on both sides of the border fear a significant escalation of violence between the drugs empires, stoked by their links to IRA splinter groups who can obtain high-powered weapons for them. In Dublin, one crime syndicate is believed to have links to the Continuity IRA.

But a source said most of the explosives and arms are still under the control of former Provos behind an Ulster-based group calling itself simply the IRA.

The northern republican source, who spent periods in jail for terrorist-related activities during The Troubles, told The Telegraph: “It will be used exclusively for republican issues.

“There will be ‘ops’ on the ‘mainland’, specific targets, the aim will be to make the Brits rethink their whole position as to what Sinn Fein is actually in a position to deliver, namely they can’t deliver peace.

“Among the targets will be those sorts of far-right industrialists, wealthy individuals who support the continued occupation of our country and also on certain political elements.

“There will be no civilian targets, whatsoever, whatever the delay to us.

“So there will be no indiscriminate attacks, not in any shape or form, meaning there will be no car-bombs. But there will be specific targets that will have the desired effect on the British economy and opinion.”

Last year the Government warned that republican terror groups are capable of carrying out “one-off” attacks on the British mainland and are sufficiently armed to pose an “enduring threat”.

MI5 warned the threat from such groups is four times greater than figures suggest and some are reverting to old Provisional IRA methods.

For every dissident attack in Northern Ireland the Security Service is helping to foil three to four, the head of the spy agency has said.

In a recent report David Anderson QC, the independent reviewer of counter-terrorism legislation, said: “Northern Ireland’s progress towards a post-conflict society is unfortunately far from complete.

“A real terrorist threat persists in parts of Northern Ireland.”

Meanwhile paramilitary-style murders and punishment beatings remain a regular occurrence in Northern Ireland.

All of the paramilitary groups that ostensibly laid down their weapons as part of the 1998 Good Friday Agreement have since committed murders.

In the past two years there have been 121 shootings in Northern Ireland, 100 bombings, 109 casualties of “paramilitary style assaults”, 45kg of explosives seized, 103 firearms and 7,162 rounds of ammunition found.

The links between current or former paramilitarists and criminal gangs, and the passing of weapons between them, has raised fears that gang violence could reach an “unprecedented” scale.

The murder in Dublin of crime lord David Byrne was carried out by men who stormed a boxing weigh-in armed with AK-47 rifles thought to have come from one of the many secret dissident arms dumps.

Days later Eddie Hutch Sr, whose brother heads the gang thought to be behind Mr Byrne’s murder, was shot dead at his home in Dublin.

The two gangs, one led by former heroin dealer Christy Kinahan from his home in Spain, the other loyal to ex-bank robber Gerry “The Monk” Hutch, had co-existed in relative peace but the murder in Spain last year of Hutch’s nephew Gary, 34, in Marbella, broke the peace and led to the murder of Byrne, one of Kinahan’s most trusted deputies.

A heavily-armed Garda Emergency Response Unit (ERU) unit has been established in Dublin as a response to the murders. On Friday night armed police threw a ring of steel around the venue for David Byrne’s wake in the Dublin suburb of Crumlin, while heavily armed vehicle checkpoints were set up around the family’s home. It signalled a determination by police not to find themselves outgunned by the criminal gangs, even at funerals.