Britain’s Heathrow Air­port was closed all day af­ter a fire at a near­by elec­tri­cal sub­sta­tion knocked out its pow­er, dis­rupt­ing flights for hun­dreds of thou­sands of pas­sen­gers at Eu­rope’s busiest trav­el hub.

Britain’s Heathrow Air­port was closed for the day af­ter a fire knocked out its pow­er overnight, dis­rupt­ing flights for hun­dreds of thou­sands of pas­sen­gers at Eu­rope’s busiest trav­el hub.

At least 1,300 flights to and from Heathrow were af­fect­ed al­ready, in­clud­ing sev­er­al from U.S. cities that were can­celled, flight track­ing ser­vice Fligh­tRadar 24 said.