A search operation is under way for a Coast Guard helicopter missing off the west coast.
The "major sea search" is being carried out around 10km west of Black Sod in Co Mayo after the Search and Rescue (SAR) helicopter with four crew on board lost contact at 1am.
The Dublin based Rescue 116 Sikorsky S-92 was providing support for Sligo's Rescue 118 aircraft when contact was lost.
SAR helicopters from Sligo and Shannon are involved in this morning's search, along with an Aer Corps plane, lifeboats from Ballyglass and Achill and five local fishing boats.
In a statement, the Coast Guard said the Sligo-based R118 helicopter completed a medical evacuation of a crewman requiring urgent medical attention from a UK-registered fishing vessel 240km west of Eagle Island in Co Mayo early this morning.
"Owing to the distance involved, safety and communication support, known as Top Cover, was provided by the second Coast Guard helicopter, the Dublin-based R116," the statement said.
Both of the helicopters re-fuelled at Black Sod before travelling to the scene.
Ger Hegarty, the Divisional controller at the Marine Rescue Coordination Centre in Dublin, he says there was no indication that the helicopter had run into difficulty.
"We lost contact with them about six miles, five or six miles off the coast, and the search is ongoing.
"We lost contact at about 1am this morning with the helicopter. There is four crew on board," he said.UPDATE :: 7.59am
Wreckage found by Sligo's Rescue 118 plus one crew member survivor in 'critical' condition.He is now on board a lifeboat being brought ashore however their is serious concern for his wellbeing with early reports from the Coast Guard indicating doubt of his survival.
The search for the other three continues.
The naval vessel LE Roisín has also joined the search.
Navy divers are on site.
The coastguard say debris has been found spread over a wide area.
Eugene Clonan Head of Operations of the Irish Coast Guard has said "hopes are fading" of finding the remaining crew.No prior warning
The Search and Rescue Operations Manager of the Irish Coast Guard has said there was no prior warning before a Search and Rescue helicopter went missing off the Co Mayo coast in the early hours of this morning.
Gerard O'Flynn said there has been no indication about what happened, and that the Air Accident Investigation Unit will be conducting a full investigation into the incident.
"This was a shock, the helicopter just simply disappeared. Communications was lost. Once communications was lost, an emergency procedure was initiated, a search was immediately initiated. But it was just a sudden break in communication and there was no prior warning of any particular problem," he said. UPDATE :: 2.15pm
It has now been confirmed that the captain of the ill-fated Rescue 116, Dara Fitzpatrick has died.
Captain Fitzpartick was taken ashore earlier by lifeboat. She was a well-known senior pilot with the service.
Captain Dara Fitzpatrick, pictured right,
has died. Photo: Irish Coast GuardSee Related Articles above