The Department of Transport's air accident investigation unit and gardaí have initiated separate inquiries into the cause of a helicopter crash which claimed the lives of two Galway businessmen at the weekend.
The Robinson R44 helicopter with three people on board was returning to Galway from Waterford when it is believed to have hit mist and fog in the Slieve Aughty mountains.
It crashed in forestry close to the wind farm site at Derrybrien in south Co Galway shortly after midday on Saturday.
One of the men on board raised the alarm on his mobile phone, and air traffic controllers at Galway Airport diverted another helicopter to the area to try and locate the crash site.
Damien Bergin subsequently died in hospital, along with passenger Mark Reilly.
Mr Bergin, who was single and in his 30s, was from Castleblakeney, east Galway. He worked formerly as a sales manager in the motor trade and had set up a construction development company, Hyberg Construction. It was involved in a housing plan for Spiddal, Co Galway, which was the subject of a Bord Pleanála hearing last year.
Mr Reilly (49) was a father of three young children, and a well-known Galway city businessman. He part-owned the Front Door pub in the city centre and Tom Sheridan's in Knocknacarra.
The third man on board has been named as Mike Givens, a sales rep from Oranmore, Co Galway. His condition in hospital has been described as stable. It is understood that the three men had flown to Waterford on Friday for the Tall Ships race and were returning when the accident occurred.
The heavily-forested area made it difficult for emergency crews, and a helicopter from Galway and the Irish Coast Guard Sikorsky from Shannon were scrambled to assist in the search.
Fire crews had to deal with hazardous aviation fuel, and cutting equipment was used to free the men, who were flown by Sikorsky to University College Hospital, Galway. Mr Reilly died shortly after admission, and Mr Bergin died later on Saturday.
It is understood the helicopter was owned privately and leased commercially.