(CNN) — Full power has been restored to New York's John F. Kennedy airport's Terminal 1, according to a statement from the Port Authority of New York and New Jersey on Saturday.
Limited flight activity resumed at the international terminal of the airport earlier Saturday morning after "necessary electrical repairs" were completed overnight, the statement read.
"Safety and security systems are fully functional and other building systems are being tested and brought back online."
The power outage at Terminal 1 began Thursday, and the terminal remained closed throughout Friday, CNN previously reported.
Terminal 1 represents 5% of all JFK scheduled passenger flights, an earlier statement from the Port Authority said. Of the 64 arrivals and departures originally scheduled at Terminal 1 today, 26 will operate at the terminal, 28 will be handled at different JFK terminals or other local airports, and 10 were canceled, Saturday afternoon's statement said.
The outage at Terminal 1 was caused by an electrical panel failure, which resulted in a "small isolated fire overnight that was immediately extinguished," the Port Authority of New York and New Jersey said in a statement Thursday.
"The power outage is currently impacting the terminal's ability to accept inbound and outbound flights," the statement said.
Other terminals were used to accommodate the affected flights, the Port Authority said.
An Air New Zealand flight due to land at JFK at 5:40 p.m. ET Thursday was diverted back to its origin airport, according to flight tracking site FlightAware.
Some arriving international flights were diverted to other East Coast airports, including Newark Liberty International Airport in New Jersey, Boston's Logan International Airport and Washington Dulles International Airport, JFK's website showed.
Flight from New Zealand turns around midflight
Passengers on the Air New Zealand flight found themselves on a nearly 16-hour flight from Auckland back to Auckland after ANZ2 turned around because of the disruption at JFK.
"Diverting to another US port would have meant the aircraft would remain on the ground for several days, impacting a number of other scheduled services and customers," the airline said in a statement to CNN.
Airline staff will be on hand to rebook passengers when they arrive back in Auckland.
"We apologise for the inconvenience and thank our customers for their patience and understanding."
CNN's John Miller and Marnie Hunter contributed to this report.