London’s Heathrow Airport is closed, prompting global travel chaos

Firefighters and police are investigating the cause of a blaze that caused a major power outage in west London, closing Heathrow Airport.

Passengers have been asked not to travel "under any circumstances" to the airport, which had been due to have more than 1,330 scheduled flights on Friday, flying up to 291,000 passengers, according to aviation analytics firm Cirium.

Some 1,351 flights were either cancelled or forced to land elsewhere. A Heathrow spokesperson warned that significant disruption was expected over the coming days.

Counter-terrorism officers from the Metropolitan Police will be involved in the investigation, according to reports, not because of any direct evidence of sabotage, but because of the quick need to rule out foul play.

Emergency services were called to the scene at 11:23pm on Thursday. They received 212 calls about the fire on Thursday evening, and estimate that 67,000 households were left without power after the fire at the substation, with 5,000 still without power.

London Fire Brigade said the fire was under control with approximately 10% of it still alight.

Heathrow's terminals two and four were still without power at Friday lunchtime.