This frame grab taken from a UGC video shot and posted on X on March 21, 2025 by @fire_at_Vill shows a fire burning at a neighborhood electrical substation supplying power to Heathrow Airport in Hayes, west London. (Photo by Handout / Courtesy of X user @fire_at_Vill / AFP)

Britain’s Heathrow airport, Europe’s busiest, was shut down early Friday after a major fire at neighbourhood electrical substation supplying power to the sprawling facility west of London, officials said.

Several flights were already being diverted, according to flight-tracking website FlightRadar24, while airport authorities said they “expect significant disruption over the coming days”.

“Heathrow is experiencing a significant power outage,” the airport operator said in a statement on its website, adding it would be closed until just before midnight Friday (2359 GMT).

A firefighter helps putting out a fire that broke out at a substation supplying power to Heathrow Airport in Hayes, west London on March 21, 2025. Britain’s Heathrow airport, Europe’s busiest, was shut down early on March 21 for 24 hours after a major fire at an electricity substation cut power to the sprawling facility west of London, officials said. (Photo by BENJAMIN CREMEL / AFP)

“Passengers should not travel to the airport under any circumstances until the airport reopens.”

London Fire Brigade said there has been a “significant” fire at a substation in Hayes, a town in the London borough of Hillingdon.

“The fire has caused a power outage affecting a large number of homes and local businesses, and we are working closely with our partners to minimise disruption,” said assistant commissioner Pat Goulbourne said.

“This is a highly visible and significant incident, and our firefighters are working tirelessly in challenging conditions to bring the fire under control as swiftly as possible.

A departure board displays Air Portugal flight TP8418 to London Heathrow as cancelled at Singapore Changi Airport in Singapore on March 21, 2025. (Photo by Roslan RAHMAN / AFP)

A Qantas flight arriving from Perth was diverted to Paris’ Charles de Gaulle while a United Airlines flight from New York was due to land in Ireland’s Shannon instead.

Heathrow handles more than 80 million passengers a year.