The Disappeared: Meath bog to be searched for Brendan Megraw

Brendan Megraw's wife was expecting their first baby when he was abducted from his Belfast home in 1978

Forensic work is to begin next week in the search for an IRA victim whose body has been missing for almost 40 years.

The Independent Commission for the Location of Victims' Remains (ICLVR) said a 'geophysical survey' will be carried out on land not previously searched at a bog in Oristown, County Meath.

It is believed Brendan Megraw's remains are buried somewhere on the land.

He was one of the 16 murder victims that became known as the Disappeared.

Mr Megraw was 23 years old when he was abducted from Twinbrook in Belfast in 1978, and murdered by the IRA.

There have been three unsuccessful searches for him, the most recent in 2010.

His brother, Kieran Megraw, said the family were wary of getting their hopes up.

"You're thankful that information has come in," he told BBC Radio Ulster's Good Morning Ulster.

"But you have to temper your expectation and hope. You're hoping then the results of the survey will say it's okay to go ahead."

The IRA claimed that he had confessed to being a British provocateur and Military Reaction Force undercover agent.

'Not enormous'

Senior forensic investigator Geoff Knupfer told Good Morning Ulster that the latest search was a "continuation" of the previous efforts to find Mr Megraw.

"We've undertaken two or three phases previously. They're all adjoining one another which would indicate to you and your listeners that we've been told where to go, where to look and, really, it's a continuation of that process."

He added the chances of finding Mr Megraw were "not enormous" but that he was "optimistic" if the grave area has not been disturbed.

He said: "No-one, least of all Brendan's family, is under any illusion that this is anything other than a huge task.

"We will carry out an initial survey of ground that is on the site where we think Brendan could be buried, but has not previously been analysed.

"This will involve a team of forensic archaeologists using ground-penetrating radar to try to identify anomalies beneath the surface that may warrant further investigation and a fresh search."

The ICLVR was established in 1999 to obtain information in strictest confidence which may lead to the location of the remains of the Disappeared - those killed and buried in secret by banned paramilitary groups prior to 10 April 1998 as a result of the Troubles.

Information passed to the ICLVR is kept confidential and cannot be used in criminal proceedings.

The ICLVR said that over four hectares of the Oristown bog have been searched to date, with a further 2.5 hectares to be covered by the new land survey.

Two other victims - Kevin McKee and Seamus Wright - both from west Belfast and abducted in 1972, are thought to be buried nearby in Wilkinstown.