ATLANTA (CBSNewYork/AP) — A power outage at the Hartsfield-Jackson Atlanta International Airport disrupted incoming and outgoing flights through the day and night Sunday.

Airport spokesman Reese McCraine says the outage occurred early Sunday afternoon. All airport operations were affected and flights were halted.

“The lights flickered once. It was really scary, but we were like, hopefully nothing happens,” said stranded traveler Muhammad Saeed. “And then they flickered again and they didn’t come back.”

“At first I was like, gosh, what’s going on? It could be weather,” said stranded traveler Cierra Klett. “And then I noticed that it kept flickering and finally it went off. I was like, oh no.”

The Federal Aviation Administration, meanwhile, implemented a “ground stop” for flights headed to the airport. A ground stop means that flights headed to Atlanta are held on the ground at their departure airport.

The total number of delays at the airport in Atlanta on Sunday amounted to 522 as of the 5 p.m. hour, while the total number of cancellations amounted to 714. The number increased as the night went on.

Delta Airlines alone reported later Sunday that it canceled about 900 flights and diverted 48 to other airports, and said 300 more flights are expected to be canceled on Monday.

A total of four flights to John F. Kennedy International Airport from Atlanta were canceled, while one was delayed. Three fights to Atlanta from JFK were also canceled and one was delayed.

A total of 14 flights that were headed to LaGuardia Airport from Atlanta were canceled, along with 16 flights to Atlanta from LaGuardia. Three flights to Atlanta from LaGuardia were also delayed, according to the Federal Aviation Administration.

Power returned to the atrium and concourses T, A and B late Sunday night, the airport reported.

In a news release Sunday evening, the utility said the “the issue may have involved a fire which caused extensive damage in a Georgia Power underground electrical facility.” The cause of the fire was not known, the statement says, but it impacted underground facilities and substations serving the airport.

Georgia Power spokeswoman Holly Crawford had said earlier that only the airport had been affected by the outage.

(© Copyright 2017 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)