Heathrow Airport in West London announced on Saturday morning that it was in full operation again, the day after the closure caused by the power outage from the fire that broke out in a nearby power substation and caused chaos in air transport.

The closure of Europe’s busiest airport yesterday led to more than 1,000 cancellations and problems on traveling more than 200,000 passengers.

In a statement on Friday night, the Metropolitan Police said the fire was probably due to system damage rather than suspicious action, while the London Fire Service (LFB) said its investigation would focus on distribution equipment.

Heathrow’s leader Thomas Goldbai said some flights began to run on Friday night in an attempt to alleviate the problems.

Several airlines, including British Airways (BA), Air Canada and United Airlines, said late Friday that they would restart scheduled flights to and from Heathrow.

Thomas Goldbai added that passengers planning to fly from Heathrow on Saturday should come to the airport in time for the flight, adding that “there is no reason to come earlier”.

“We expect to be back in full operation (Saturday), so in 100% operation like a normal day,” he said

At the same time, he apologized to passengers whose trips were postponed, but added that the airport had to close as there were “serious security concerns”.

British Airways, who has a great presence in Heathrow, said she expects about 85% of her scheduled flights today. The airline usually operates almost 600 flights to and from the airport on Saturday, but it is reasonable that there will be cancellations mainly on high frequency routes.

A airline spokesman said: “We plan to make as many flights as possible to and from Heathrow on Saturday, but recovering a business of our size after such an important incident is extremely complicated.”

“We expect about 85% of the Heathrow program on Saturday, but it is likely that all travelers will be delayed as we continue to face the challenges caused by Friday’s power outage at the airport.”