Searchers for one of the last three men still “missing” after being murdered by the IRA during The Troubles in Northern Ireland are quietly confident his remains will be found in a new hunt.

The search is centered on a one-acre site in a Co. Monaghan bog for the remains of Columba McVeigh, from Donaghmore, Co. Tyrone, who was kidnapped at the age of 19 in November 1975 and murdered after allegedly confessing to being a British Army agent instructed to infiltrate the IRA.

The search of Bragan Bog, near Emyvale – the fifth hunt for McVeigh’s remains – started on Monday.

It is organized by the Independent Commission for the Location of Victims' Remains (ICLVR) established by an intergovernmental agreement between the Irish and British governments in 1999.

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ICLVR investigator Jon Hill, who has taken charge of the initial phase of the search, said, “We carried out a scoping exercise earlier in the year and are now concentrating on an area of around one acre in size.

“While that is relatively small compared to some of the searches we’ve carried out in the past, each one presents its own challenges and so I don’t want to put a definitive time frame on it.

“Obviously we hope that we have an early success but if that’s not the case then we’ll press on for as long as it takes.

 “Ideally, we're going to find his remains. We have the right equipment, we have the right experts.”

Fifth search for body of Disappeared murder victim Columba McVeigh https://t.co/sWXztvxGVo pic.twitter.com/XN5tGHvFdB

— Irish Examiner (@irishexaminer) September 18, 2018

McVeigh’s sister Dympna Kerr spoke of the family’s heartbreak.

“For years I couldn’t bring myself to stand on that bog where we were eventually told that Columba was buried. I went to it earlier this year and it’s a bleak and desolate place, and I cannot bear the thought that Columba is out there when he should be beside our mum and dad,” she said.

'I pray this torment will end' - sister of missing Columba McVeigh as new dig begins today https://t.co/fYU3I4sERH pic.twitter.com/Mmzyt1uAiH

— Independent.ie (@Independent_ie) September 17, 2018

“Knowing that the ICLVR will do everything they possibly can to bring Columba home and also knowing that we have the thoughts and prayers of the other families of the disappeared gives me the strength to face the coming days and weeks.”

In the disappeared list of 16, 13 bodies have already been recovered.

Remains still to be found include those of former Cistercian monk Joe Lynskey who joined the IRA which later “executed and buried” him, and British army captain Robert Nairac who was abducted by the IRA in a Co. Armagh pub car park in May 1977.

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Columba McVeigh, from Donaghmore, Co. Tyrone.