More than 1,300 flights were affected after a fire at a nearby electrical substation. Hundreds of thousands of passengers were stranded around the world.

London's Heathrow Airport​, one of the busiest airports in the world, was shut down by a power outage caused by a fire at an electrical substation.

London's Heathrow Airport, one of the busiest in the world, reopened Friday night, 19 hours after flights were halted because of a "significant power outage," the airport said.