On the 21st anniversary of the attacks on September 11, 2018, police responded to "reports of a suspicious package" at Newark Airport.
Which resulted in the evacuation of a portion of the airport and the delay of dozens of flights, according to officials from the Port Authority.
Officials say that when police learned about the package at 12:45 p.m., they "immediately" cleared out the lower level of Terminal C "as a precaution."
At 1:45 p.m., officials gave the "all clear" and started running the terminal again, but passengers were already feeling the effects of the slowdown.
Officials from the FAA confirmed that a ground stop had been ordered for a United Airlines flight leaving from Terminal C between 1:30 and 2:30.
A spokesperson for the Port Authority said that the short-term evacuation caused about 59 flights to be late.
Concerned passengers took to social media to voice their lack of understanding regarding what was taking place.
"America is stuck in Newark airport on the worst day in our recent history, and travellers are scared because they don't know what's going on," a frustrated passenger wrote on Twitter.
Numerous tweets inquired, "Anyone know what's going on at Newark Airport that's causing a security shutdown, trapping us, and causing us to miss flights?"