THE Irish army has completed a confidential mapping of the Northern Ireland border ahead of Brexit that has found substantially more routes into the region than previously thought.
The mapping exercise is believed to have identified almost 300 crossing points across the 310-mile frontier, including many routes that had not been officially recorded before, according to informed sources.
The routes are understood to include country lanes, private roads, rights of way across private lands and other unmarked access points leading into Northern Ireland that have the potential to be smuggling routes.
The highly sensitive work was conducted by members of the Irish Defence Forces, working with gardai. It involved a physical mapping of the border by army personnel along with desk-top work and was completed in recent months.
The Republic's defence forces are continually mapping the border for security purposes, such as during the foot and mouth disease outbreak 17 years ago.
The latest exercise is regarded as particularly significant in light of the potential security risks posed by Brexit.
The updated map of the frontier will form a key part of the security services' contingency planning for a doomsday scenario that could follow Britain plunging out of the EU without a deal.
The last report on the border by authorities on both sides of the border in July identified 208 official crossing points.
However, it highlighted only public roadways along the border and did not include any private roads or laneways.
The survey highlighted scores of private crossing points, some of which could be vulnerable to criminality in the event of a hard border. The Irish Army's border mapping work can be viewed in the context of the security risks posed by Brexit, which were outlined in stark detail at a cross-border crime conference last month.
Garda Commissioner Drew Harris told the conference that dissidents would "undoubtedly" attempt to exploit a hard border as "something they wish to rally around".
But the conference was also warned that even a soft Brexit could lead to challenges, with increases in cross-border smuggling of all kinds, including people trafficking, cigarette and alcohol smuggling and fuel laundering.
The conference was told that 43% of cross-border gangs are highly mobile and operate on both sides of the border.
Previous security assessments have identified 10 criminal gangs dominating cigarette smuggling on both sides of the border.
The Irish government's position is that there must be no return to a hard border.