Photo: AP Photo/Kin Cheung

A traveller 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.

All arriving flights in Toronto from Heathrow have been cancelled after an overnight fire caused a power outage and forced the British airport to close for the day, Pearson airport said.

As of early Friday, Pearson airport listed at least five scheduled arriving flights from Heathrow as cancelled, as well as two departing flights.

Those flights were among the at least 1,300 flights to and from Heathrow that have been impacted by the closure and have been diverted or cancelled, according to flight tracking service FlightRadar 24.

Pearson spokesperson Erica Vella said passengers are advised to check the status of their flight with their airline.

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 has been contained but firefighters will remain on scene throughout Friday.

The airport said it expects "significant disruption" over the coming days, and passengers should not travel to Heathrow. The closure has disrupted the travel plans of about 200,000 people who were expected to travel through Heathrow on Friday.

Police in London said there’s no indication of foul play in the fire, but counterterror detectives are leading the investigation that shut down Europe’s busiest travel hub.

Heathrow was Europe’s busiest airport last year, with 83.6 million passengers travelling through the airport.