A construction mishap affecting air traffic control equipment in New Jersey on Monday has caused chaos for travelers flying through the Northeast — and the disruptions are piling up.

New Jersey's Newark Liberty International Airport has been under a ground stop since around 10 a.m., when a nearby air traffic control center experienced an equipment outage, forcing the Federal Aviation Administration to halt inbound flights.

The outage has since affected Philadelphia and New York's JFK and LaGuardia airports, with hundreds of flights delayed, diverted, or canceled. Newark has been hit hardest so far, with about 500 departing and arriving flights canceled — over a third of all scheduled operations.

LaGuardia and JFK have seen only a handful of cancellations, but nearly 300 have been delayed at each. About 100 flights have been canceled in Philadelphia, with about another 250 delayed.

FAA Administrator Bryan Bedford told CBS News around 1 p.m. that the primary circuit, which was old and due for replacement, failed, and that about 600 feet of the backup fiber was accidentally cut out by a construction crew.

He said the backup could take half a day to repair, but the primary circuit would take about 30 minutes. About an hour later, the FAA told CBS News that the fix didn't work. The affected ATC facility is the Philadelphia Terminal Radar Approach Control, or TRACON, which manages arriving and departing aircraft in the area.

Transportation Secretary Sean Duffy said in an update on X around 3 p.m. Monday that the outage was caused by an "Amtrak construction crew" who "accidentally cut into a fiber line." He said flights are resuming in LaGuardia and Philadelphia, but flights into Newark and JFK are still paused. Flights into Teterboro, an airport primarily used for private aviation, are also paused.

Flightradar24 shows that several Newark-bound flights have diverted to destinations such as Pittsburgh and Detroit. A United flight from Bogota to Newark diverted halfway through to Orlando. Flights from Europe on Lufthansa and Swiss were seen turning around over the Atlantic.

Verizon told Reuters that it was their fiber cable, but that it was not their technicians who cut it: "We immediately deployed our technicians to the scene," a spokesperson said. "We and our partners are actively working to repair the damaged cable and restore connectivity as quickly as possible."

It's unclear when the issue will be resolved, but it's likely to snowball into the evening and potentially into Tuesday. It's also unclear if airlines — who would not be considered at fault for the disruptions — will offer any accommodations or compensation for those stranded.

Flyers should continue to monitor their flight status, and those who booked with travel credit cards may have options for delays or trip reimbursement.