Newark Liberty International Airport was hit by a power outage Monday afternoon.
A media alert from utility company PSE&G appeared to attribute the outage to a equipment failure in one of the company's switching station yards.
"While in the process of upgrading PSE&G's Bayway Switching Station in Elizabeth, an equipment failure occurred in the switching station yard at about 2:30 p.m. Electric service was interrupted at Newark Airport and in parts of Hillside, Elizabeth, Union, Newark, Roselle, Linden, Kenilworth and Irvington. Approximately 20,000 customers have been impacted by the outage," the alert read, adding that crew were working to isolate the issue and restore service.
Sources in the airport earlier told CNBC that the outage left all terminals without electricity but that flights still appeared to be taking off.
"I’m looking at planes taking off and landing,” said traveler Bill Walsh, who said he boarded his American Airlines flight for Dallas after a roughly 30-minute delay.
A spokesperson for the New York and New Jersey Port Authority confirmed to CNBC that "parts of terminals A B and C are without power," but would not comment on potential flight delays.
--Ryan Ruggiero contributed to this report.