A traveller speaks on the phone at the entrance to Terminal 4 as Britain's Heathrow Airport has closed for the full day after an electrical substation fire knocked out its power, disrupting flights for hundreds of thousands of passengers at one of Europe's biggest travel hubs in London, Friday, March 21, 2025.(AP Photo/Kin Cheung)
TORONTO — Several arriving and departing flights between cities across Canada and London’s Heathrow Airport were cancelled after an overnight fire caused a power outage and forced the British airport to close Friday,with further flight disruptions expected to last for days.
As of early Friday, Toronto’s Pearson airport listed at least five scheduled arriving flights from Heathrow as cancelled, as well as two departing flights. Airports in Vancouver and Montreal also listed multiple cancelled flights.
Those flights were among at least 1,300 to and from Heathrow that were affected by the closure and either diverted or cancelled, according to flight tracking service FlightRadar 24.
Heathrow said Thursday that a fire at an electrical substation that supplies power to the airport caused the outage. The London Fire Brigade said the fire was contained but firefighters would remain on scene throughout Friday.
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Britain London FIre Stranded passengers makes their way down unlit stairs due to lifts not working to the car park at Heathrow Terminal 4 in London, Friday March 21, 2025, as consequence of the closure of the airport following a fire at the North Hyde electrical substation last night. (James Manning/AP)
Britain London Fire Firefighters extinguish the fire at the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025.(AP Photo/Kirsty Wigglesworth) (Kirsty Wigglesworth/AP)
Britain London Fire This image taken from video shows firefighters working to secure the area of a fire at the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025. (Sky News via AP) (Sky News/AP)
Britain London Fire This image taken from video shows firefighters working to secure the area of a fire at the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025. (Sky News via AP) (Sky News/AP)
Britain London Fire This image taken from video shows firefighters working to secure the area of a fire at the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025. (Sky News via AP) (Sky News/AP)
Britain London Fire This image taken from video shows firefighters working to secure the area of a fire at the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025. (Sky News via AP) (Sky News/AP)
APTOPIX Britain London Fire Firefighters extinguish the fire at the North Hyde electrical substation, which caught fire Thursday night and led to a closure of Heathrow Airport in London, Friday, March 21, 2025.(AP Photo/Kirsty Wigglesworth) (Kirsty Wigglesworth/AP)
Britain London Fire This image taken from video shows parked planes at Heathrow airport, as a fire at the North Hyde electrical substation on Thursday night has led to a closure of Heathrow Airport in London, Friday, March 21, 2025. (Sky News via AP) (Sky News/AP)
Britain London Fire This image taken from video shows an empty taxi drop-off area of Heathrow airport, as a fire at the North Hyde electrical substation on Thursday night has led to a closure of Heathrow Airport in London, Friday, March 21, 2025. (Sky News via AP) (Sky News/AP)
India London Fire Passengers wait for the information on flights destined for the Heathrow Airport in London, outside the Indira Gandhi International Airport, in New Delhi, India, Friday, March 21, 2025. (AP Photo/Shonal Ganguly) (Shonal Ganguly/AP)
Britain London Fire A worker inspects the site of the fire at the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025.(AP Photo/Kirsty Wigglesworth) (Kirsty Wigglesworth/AP)
Britain London Fire Planes are parked at the Terminal as Britain's Heathrow Airport has closed for the full day Friday after an electrical substation fire knocked out its power, disrupting flights for hundreds of thousands of passengers at one of Europe's biggest travel hubs in London, Friday, March 21, 2025.(AP Photo/Kin Cheung) (Kin Cheung/AP)
Britain London Fire Workers inspect the site of the fire at the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025.(AP Photo/Kirsty Wigglesworth) (Kirsty Wigglesworth/AP)
Britain London Fire Smoke still rises as firefighters inspect the site of the fire at the North Hyde electrical substation, which caught fire Thursday night and lead to the closure of Heathrow Airport in London, Friday, March 21, 2025.(AP Photo/Kirsty Wigglesworth) (Kirsty Wigglesworth/AP)
Britain London Fire A treveller speaks on the phone at the entrance to Terminal 4 as Britain's Heathrow Airport has closed for the full day Friday after an electrical substation fire knocked out its power, disrupting flights for hundreds of thousands of passengers at one of Europe's biggest travel hubs in London, Friday, March 21, 2025.(AP Photo/Kin Cheung) (Kin Cheung/AP)
Britain London Fire A traveller arrives with his lugage at Terminal 4 as Britain's Heathrow Airport has closed for the full day Friday after an electrical substation fire knocked out its power, disrupting flights for hundreds of thousands of passengers at one of Europe's biggest travel hubs in London, Friday, March 21, 2025.(AP Photo/Kin Cheung) (Kin Cheung/AP)
Britain London Fire Traveller arrive with their lugage at Terminal 4 as Britain's Heathrow Airport has closed for the full day Friday after an electrical substation fire knocked out its power, disrupting flights for hundreds of thousands of passengers at one of Europe's biggest travel hubs in London, Friday, March 21, 2025.(AP Photo/Kin Cheung) (Kin Cheung/AP)
Britain London Fire Travellers walk through the dark car park at Terminal 4 as Britain's Heathrow Airport has closed for the full day Friday after an electrical substation fire knocked out its power, disrupting flights for hundreds of thousands of passengers at one of Europe's biggest travel hubs in London, Friday, March 21, 2025.(AP Photo/Kin Cheung) (Kin Cheung/AP)
APTOPIX Britain London Fire Firefighters extinguish the fire at the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025. (AP Photo/Kirsty Wigglesworth) (Kirsty Wigglesworth/AP)
Britain London Fire Lugage trolleys are parked as Britain's Heathrow Airport has closed for the full day Friday after an electrical substation fire knocked out its power, disrupting flights for hundreds of thousands of passengers at one of Europe's biggest travel hubs in London, Friday, March 21, 2025.(AP Photo/Kin Cheung) (Kin Cheung/AP)
Britain London Fire Smoke still rises as firefighters inspect the site of the fire at the North Hyde electrical substation, which caught fire Thursday night and lead to the closure of Heathrow Airport in London, Friday, March 21, 2025.(AP Photo/Kirsty Wigglesworth) (Kirsty Wigglesworth/AP)
Britain London Fire No travellers are seen inside Terminal 4 as Britain's Heathrow Airport has closed for the full day Friday after an electrical substation fire knocked out its power, disrupting flights for hundreds of thousands of passengers at one of Europe's biggest travel hubs in London, Friday, March 21, 2025.(AP Photo/Kin Cheung) (Kin Cheung/AP)
India London Fire Traveller Lauren Clark, left, and Shahin Jade Ali wait at Chhatrapati Shivaji Maharaj International Airport after a fire at Heathrow Airport in London forced its closure, leading to numerous flight cancellations, in Mumbai, India, Friday, March 21, 2025. (AP Photo/Rajanish Kakade) (Rajanish Kakade/AP)
Britain London Fire Workers inspect the site of the fire at the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025.(AP Photo/Kirsty Wigglesworth) (Kirsty Wigglesworth/AP)
India London Fire A passenger stands in front of a flight information screen showing cancelled flights destined for the Heathrow Airport in London, at the Indira Gandhi International Airport, in New Delhi, India, Friday, March 21, 2025. (AP Photo/Shonal Ganguly) (Shonal Ganguly/AP)
Britain London Fire This photo provided by London Fire Brigade, shows a fire at the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21 2025. (London Fire Brigade/AP)
Britain London Fire Firefighters extinguish the fire at the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025. (Kirsty Wigglesworth/AP)
Britain London Fire Firefighters extinguish the fire at the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025. (Kirsty Wigglesworth/AP)
Britain London Fire A sign on the motorway shows Heathrow Closed as Britain's Heathrow Airport has closed for the full day Friday after an electrical substation fire knocked out its power, disrupting flights for hundreds of thousands of passengers at one of Europe's biggest travel hubs in London, Friday, March 21, 2025. (Kin Cheung/AP)
Britain London Fire Firefighters extinguish the fire at the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025. (Kirsty Wigglesworth/AP)
Britain London Fire Firefighters wait at the area around the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025. (Kirsty Wigglesworth/AP)
Britain London Fire Firefighters wait at the area around the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025. (Kirsty Wigglesworth/AP)
APTOPIX Britain London Fire Firefighters extinguish the fire at the North Hyde electrical substation, which caught fire Thursday night and led to a closure of Heathrow Airport in London, Friday, March 21, 2025. (Kirsty Wigglesworth/AP)
Britain London Fire Police forces cordon off the area around the North Hyde electrical substation, which caught fire Thursday night and lead to a closure of Heathrow Airport in London, Friday, March 21, 2025. (Kirsty Wigglesworth/AP)
Britain London Fire In this image taken from video provided by @fire_at_Vill, Emergency services at the scene of a fire at an electrical substation near Heathrow Airport, in London, Friday, March 21, 2025. (@fire_at_Vill/AP)
Heathrow had said it didn’t know when power would be restored and it expected the disruption to last for days. In an update Friday afternoon, Heathrow said it’s now able to restart flights and will prioritize “repatriation and relocation of aircraft.” It said the first plane to land since the outage arrived 18 hours after it began.
The airport said it hopes to be fully operational on Saturday.
The closure disrupted the travel plans of about 200,000 people who were expected to travel through the airport on Friday.
Air Canada said Friday that six of its flights on Thursday were diverted mid-air while a seventh was cancelled before departing. Those flights included some from routes through Toronto, Montreal and Calgary.
The airline said early Friday it had cancelled 16 flights in total, including return flights from London. In a later update, Air Canada said it planned to operate its regular schedule of flights starting Friday evening after flights resumed at Heathrow.
Air Canada previously said it rerouted some customers to other European gateways and was helping passengers bound for London to change their travel plans.
WestJet said in a statement that two of its flights between Calgary’s international airport and Heathrow were cancelled Thursday and Friday. The airline said no further cancellations were expected, but passengers were advised to check the status of their flight before going to the airport.
Police in London said there was no indication of foul play in the fire, but counterterrorism detectives were leading the investigation that shut down the airport.
A spokesperson for U.K. Prime Minister Keir Starmer said there must be a “rigorous investigation” into how a single fire could shut down Europe’s busiest travel hub.
Heathrow chief executive Thomas Woldbye apologized Friday for the daylong closure, but said there was no choice but to shut down the airport for safety reasons.
Heathrow was Europe’s busiest airport last year, with 83.6 million passengers travelling through it.
With files from The Associated Press.
This report by The Canadian Press was first published March 21, 2025.