One of the biggest airports in the world is closed.

Following a devastating electrical fire, London’s Heathrow Airport has been closed all day, causing severe power outages and causing chaos in the travel industry.

Experts caution that the disruption, which is affecting hundreds of thousands of passengers, could continue for days and have an impact on people all over the world.

A substation for electricity exploded.

Early on Friday morning, Heathrow’s official X account made the following startling announcement:

Heathrow is facing a severe power outage as a result of a fire at an electrical substation that supplies the airport. In order to ensure the security of our travelers and coworkers, Heathrow will be closed until 23:59 on March 21. It is recommended that passengers contact their airline for more information and avoid going to the airport. We regret any inconvenience this has caused.

Additionally, a Heathrow representative informed British media that flight delays are anticipated to continue for a few days.

Heathrow itself is not on fire, but a fire close by has caused so much disruption to operations that the airport is unable to continue operating. A transformer building in Hayes, about two kilometers (1.2 miles) from Heathrow, is where the fire began, according to Sky News. The severe power outage was caused by an explosion in the airport’s main electrical substation.

Around 200,000 passengers were set to travel through Heathrow today, but the airport’s closure has sparked major disruption that will likely continue into the weekend and beyond.

The fire started around 11:30 PM Thursday night, and although firefighters worked through the night to control it, part of the transformer building is still burning. Police have declared a major incident, and investigators are looking into the cause.

By morning, the fire had been extinguished, but specialist firefighters were still working to dampen the area using breathing apparatus.

”This was a very visible and significant incident, and our firefighters worked tirelessly in challenging conditions to bring the fire under control as swiftly as possible,” assistant commissioner Pat Goulbourne said.

The decision to shut down the airport due to the failure of one substation raises serious concerns. While Heathrow officials have confirmed that backup power systems are in place, activating these contingencies takes time and is not an immediate fix.

At least 1,357 flights have been delayed, canceled, or diverted, according to Daily Mail. Many airports, including Gatwick, are now at capacity, while some flights that were already headed to London have landed at other airports.

Other airports in Europe are preparing for a surge of aircraft that need to be rerouted because they are too far into their flights to turn back as the chaos continues.

One of the busiest airports in the world for international travel, Heathrow, saw a record-breaking January this year, handling over 6.3 million passengers, a more than 5% increase over the same period last year. Additionally, the airport saw an average of over 200,000 passengers per day for the eleventh consecutive month, with transatlantic flights contributing significantly to the increase.

National Rail has announced the cancellation of rail services to and from Heathrow on Friday in addition to the disruptions to flights.