A MAJOR search operation is underway today in an attempt to trace the whereabouts of an Irish man who went missing on the Australian coast a week ago.

Mystery still surrounds details of the background of 30-year-old Niall McDonough who disappeared in Byron Bay, New South Wales.

Australian police have been unable to provide information on where McDonough originates from in Ireland and his family has appealed for privacy.

A spokesman for the New South Wales police force said: "I don't believe we have been provided with that information yet; I don't believe [the investigators] have ascertained that at this stage."

Members of the missing man's family arrived in Byron Bay on Thursday where they were updated by police, although they have asked local media for privacy and will not, at this stage, make any public statements.

A source close to the investigation said the reason for some confusion over McDonough's background is due to his family being "spread over a number of locations". It is understood his parents may not have been in Ireland at the time of his disappearance.

Information leaflets on McDonough – who went missing after going for a walk on the night of Friday 12 June – have been circulated to local hostels.

A major search operation covering land and sea was launched today, including local police, the police rescue squad, volunteers from the state emergency service and the surf rescue.

"There will be a full-scale search carried out in the area where his belongings were found on Sunday; there have been no sightings or information provided to the police," a spokesman said.

Searchers will focus on the area around the Cape Byron lighthouse where the belongings were found.

The Department of Foreign Affairs confirmed it is offering consular assistance to the family, but declined to comment further.

McDonough was last seen by his girlfriend before he went missing. Her identity has also been kept confidential although local sources say the couple may not have been together for very long.

The search for McDonough is one of two ongoing searches in relation to missing Irish men.

Sean Walsh (26) from Dungarvan in Waterford has been missing since 10 May when he went walking in Sydney with friends.

His parents John and Helena have both now travelled to Sydney to help in efforts to locate him. His disappearance has been described as extremely out of character.

Walsh had been on an around-the-world trip, working in ski resorts before ending up in Australia.

His family set up the www.seanwalshmissing.com website, appealing for information on his whereabouts.