A call by Ukip's Northern Ireland leader for David Cameron to deploy the British army along the border in the event of a Brexit has been dismissed as "fantasy".
Former Strangford MLA David McNarry claimed "jihadis" could copy the IRA and travel from the Republic to Britain via Northern Ireland.
The one-time Ulster Unionist and former Orange Order assistant grand master said leaving the 310-mile border without armed patrols if the UK votes to leave the EU next month would spark an influx of migrants, people traffickers and criminals.
"I support patrols, active patrols – we need to have the army asserting our sovereignty," he said.
"It's a hell of a job to ask anybody to do but if you leave it then it's wide open for migration, for the clever traffickers, for the criminals. They need to see that we're here and we'll do everything we can to stop people who wish us harm crossing the border."
Mr McNarry told The Express newspaper that "busloads of foreigners" were regularly driving from Dublin across the border to Larne, where they boarded ferries to Scotland and "disappeared".
Earlier this year Secretary of State Theresa Villiers insisted there would be no reason to change border arrangements in the event of a Brexit, although this appeared to be contradicted by Leave campaign chairman Lord Nigel Lawson.
Tom Kelly, chair of the Northern Ireland Stronger in Europe campaign, dismissed Mr McNarry's comments yesterday.
"If there was ever proof that Brexit cheerleaders in chief would play fast and loose with our peace and our good relations with our closest neighbour and major trading partner this has to be it.
"The stark reality of a future outside the EU as envisaged by Mr McNarry and others is one based on fantasy, fanaticism and a reckless disregard for everything Northern Ireland has fought hard to gain."
