Heathrow Airport will be closed all day Friday after a nearby fire caused a power outage.Heathrow is advising passengers not to travel to the airport and to contact their airlines.More than 1,300 flights are expected to be affected.

A giant fire near one of the world’s busiest airports knocked out power, and the cause was under investigation. Hundreds of flights were canceled or rerouted, and analysts said disruptions could last days.

Eurocontrol, the organization that controls air traffic in Europe, stated on its website that flights are not being allowed to land at Heathrow due to the power outage.