London's Heathrow Airport — one of the world's busiest — was closed on Friday due to a "significant power outage" caused by a fire at a nearby power station. An estimated 200,000 travelers could be affected.

London's Heathrow Airport, one of the busiest in the world, closed on Friday due to a "significant power outage," it said.

The London airport, which is one of the world’s busiest for international travel, said it expects “significant disruption over the coming days” and warned passengers not to come until it reopens.