Heathrow – the UK’s and Europe’s busiest airport – closed for hours until about 6pm on Friday while thousands of homes were left without power in the area. Counterterrorism detectives confirmed last week the matter is no longer ‘a potentially criminal matter’ after they were called in to investigate the fire.

Heathrow Airport was warned about the "resilience" of its power supply in the days before a fire which shut down the airport for more than a day last month. Nigel Wicking, chief executive of Heathrow Airline Operators' Committee,

The official told a parliamentary committee that he had raised concerns about the resilience of Heathrow’s electricity supply just days before a fire forced the airport to shut down.