Investigators say they believe the co-pilot of the Germanwings plane that crashed into the French Alps on Tuesday deliberately crashed it.
Audio recordings reveal he hit the descent button, refused to open the cockpit door to the Pilot, and didn't issue a mayday warning.
Lufthansa - the airline which owns and operates Germanwings - has confirmed that the black box recordings from the doomed flight shows that the captain was not in the cockpit at the time of the crash.
French prosecutor Brice Robin has given chilling details of the last minutes of the flight.
"We hear several cries of the Pilot asking to access, but there's no answer from the co-pilot".
He continues "We hear at that moment breathing from inside the cockpit, and we hear this breathing until the moment of impact".
A book of condolence for the 150 victims of Tuesday's tragedy has opened at the Mansion House, and is being signed by hundreds of people from across Dublin.
