London's Heathrow Airport resumed ‘some flights’ Friday after a fire at a power station grounded planes at Europe's busiest air hub, causing travel chaos for thousands of people around the world.The electricity substation fire late on Thursday shut down the airport, leading to the cancellation or diversion of hundreds of flights and raising questions about the infrastructure's vulnerability.Planes from Heathrow serve around 80 countries, and around 1,350 flights had been due to land or take off from the airport's five terminals Friday, according to the Flightradar24 tracking website.Around 230,000 passengers use Heathrow every day – 83mn a year – making it one of the world's busiest airports.London's Metropolitan Police said the force's Counter Terrorism Command was leading the investigation into the fire given the ‘impact this incident has had on critical national infrastructure’.’While there is currently no indication of foul play we retain an open mind at this time,’ a spokesman added.Firefighters were called to the ‘highly visible’ blaze at the substation shortly after 2320GMT on Thursday and around 70 were sent to battle the fire, which was brought under control by 0800GMT Friday.The outage left 100,000 homes without power overnight. Electricity distribution network National Grid said that at around 1400GMT power had been partially restored to Heathrow as well as to local residents affected.UK Energy Secretary Ed Miliband promised that the government would do all it could to restore power to Heathrow quickly, as questions were raised about the airport's ‘resilience’.The airport shutdown left many frustrated passengers struggling to make alternative arrangements.’I had planned this journey three months ago… I've spent so much money on tickets and everything,’ said Muhammad Khalil, 28, who was booked on a flight to Pakistan to be reunited with his wife after five months. ‘You can't imagine how stressful it is for me,’ he said.
