Updated

ATLANTA -- After a roughly seven-hour outage power was being restored to a concourse at Atlanta's airport.

Airport spokeswoman Katena Carvajales says power was being restored shortly before noon and operations were returning to normal.

Carvajales says about 18 of the airport's 199 gates lost power around 5 a.m. Monday. She says the cause of the outage wasn't immediately clear.

Delta Air Lines spokesman Anthony Black says the airline canceled about two dozen flights and was forced to delay some flights into Atlanta and to move arrivals and departures from those gates to other gates.

Black says Mondays are generally busy, and this Monday is particularly busy because of the Thanksgiving holiday.