Power has now been restored to Atlanta’s Hartsfield-Jackson international airport after passengers were left in darkened terminals and more than a thousand flights were cancelled.
The world’s busiest airport handles more than 250,000 passengers and some 2,500 flights a day.
A power cut left more than a thousand flights cancelled on Sunday and hundreds more set to be cancelled today.
The airport confirmed in a statement that it had suffered a power outage shortly after 1pm yesterday, with flights expected to resume at 6am this morning local time (11am GMT).
Several major airlines including United, Southwest and American Airlines suspended their operations on Sunday.
Altanta’s mayor said the fire’s cause was under investigation and has apologised to the thousands affected.