The person who was rescued off the Mayo coast this morning has died in hospital.
Captain Dara Fitzpatrick was the only member of a crew of four to be recovered from the Rescue 116 helicopter which disappeared off radar just after 1am this morning.
It had been helping another helicopter with a medevac operation to airlift a crewman off a fishing vessel when it disappeared from radar screens.
Three others are still missing.
Earlier, the coastguard said debris had been found spread over a wide area.
Minister for Transport Shane Ross has issued a statement expressing support and sympathy to everyone involved.