A fire in an electrical substation caused a widespread power outage at London Heathrow Airport last night.

The airport will therefore be completely closed on Friday.

At least 120 aircraft in the air were forced to divert from the airport.

After a fire in a substation in Hayes, west London, late Thursday evening, all electricity was cut to Heathrow, one of the world's busiest airports.

Heathrow writes on its website that the airport will be closed all Friday:

”"In order to maintain the safety of passengers and staff, Heathrow will remain closed until 23:59 on 21 March.".

Travelers scheduled to travel on Friday are advised to stay away from the airport and contact their airline for more information.

According to Flightradar, at least 120 planes en route to Heathrow had to be diverted to other airports. The disruption to air traffic is expected to last for several days.

Tens of thousands of households without electricity

16,000 households in west and east London were also affected by the power outage, The Guardian reports.

Ten fire engines and around 70 firefighters worked to fight the fire, according to the London Fire Brigade.

Residents in the area are being urged to close windows and doors to protect themselves from the toxic smoke. Hundreds of people have been evacuated.

"This is a very serious incident and our firefighters are working tirelessly in challenging conditions to bring the fire under control as quickly as possible," said Deputy Fire Commissioner Pat Goulbourne in a statement, adding that power outages will be extended throughout the morning.

The cause of the fire is currently unknown.

Source:Svt.se