New Delhi, Sept. 22 -- Flyers across the United States faced massive disruptions to their travel plans on Monday after equipment outages stopped flights at Newark Liberty International Airport in New Jersey and Philadelphia International Airport in Pennsylvania.

More than 1,000 flights were canceled nationwide and over 6,000 were delayed on Monday, with Newark and Philadelphia hit the hardest, ABC News reported.

According to the Associated Press, the primary communications line at the Federal Aviation Administration (FAA) facility in Philadelphia had failed earlier Monday, while the backup fiber optic line was inadvertently severed by railroad construction workers.

The failures left controllers without radar or communications for hours...