London's Heathrow has been closed until midnight tonight, following a nearby fire.
The blaze at an electrical substation in west London has led to a complete power outage at the airport.
At least 3,00 flights were due to land and take off from Heathrow today, with all of those now expected to be cancelled. 20 planes were diverted midair, and passengers have been told not to travel to the terminal 'under any circumstances'.
The closure has impacted a number of flights from Ireland, with all nine flights from Dublin to Heathrow already cancelled. Shannon Airport says it's accommodating flights as needed and has team members on-site to assist with the additional passengers.
All flights from there to Heathrow have also been cancelled, and it's already facilitated six diverted flights from Toronto, Atlanta, Bridgetown Barbados, Boston, Orlando and Newark, with the first landing just before half four this morning.
Heathrow says it has no clarity on when power will be fully restored and expects significant disruption over the coming days.
Meanwhile, Ryanair has added eight extra flights to and from London, to help people affected by the Heathrow closure. The so-called 'rescue flights' are split between today and tomorrow, and will run between Dublin Airport and London Stansted.
Anyone due to fly to the airport today is advised to get in touch with their airline.
