Delta Airlines had to cancel 250 flights on Saturday due to the power outage at the Minneapolis-St. Paul airport, a company spokeswoman said.
Betsy Talton of Delta Airlines said the airline is working to rebook passengers as soon as possible.
Airport Public Affairs Manager Melissa Scovronski said the outage, which began at 8 a.m. CDT, impacted concourses A, B, C and D in Terminal 1, occupied by Delta Air Lines.
By Saturday night, power was restored to concourses A, C and D, and the problem was isolated to 16 gates in concourse B, according to Scovronski.
Scovronski said some flights may still be affected by the outage Sunday morning and urged Delta passengers to contact the airline before arriving at the airport.
The cause of the outage has not been pinpointed yet.