Earlier this week, several US airports had to delay flights after a radio communications system in Philadelphia failed and a backup fiber optic cable was cut.

It led to severe travel disruption across major airports in the country's Northeast on Monday (September 21), with airports in New York, Philadelphia, Boston, and New Jersey among those affected.

Flights were delayed across airports after a communications circuit at a control center that manages flight traffic in the Philadelphia region failed, grounding flights at Philadelphia and Newark. The infrastructure is managed by the Federal Aviation Administration (FAA).

It was a double whammy: the backup system also failed after a fiber cable was severed in New Jersey.

The cable was cut by NJ Transit, a train operator based in the state of New Jersey, which confirmed that one of its crews accidentally severed it.

Repairs on the cable were carried out by Verizon, which said it would take 13 hours to restore services, as reported by CNN.

The cable was cut at around 9:45 am ET on Monday, with Verizon telling the news outlet that the blame lay with the construction workers.

“Construction contractors working in the area dug up and cut our cable,” said Verizon in a statement. “Verizon’s facilities were fully functional up to that point. Verizon bears no responsibility for this incident.”

Transportation Secretary Sean Duffy instead chose to blame the country's aging infrastructure for the widespread disruption.

"This incident underscores the need for additional funding to modernize aging infrastructure and prevent disruptions like this in the future," said Duffy on X.