Panicked travelers abandoned carry-on bags and scrambled for the exits at a Newark Liberty International Airport terminal on Monday night, just as the busy three-day Labor Day weekend was drawing to a close.

An Alaska Airlines employee at Gate 30 in Terminal A grew suspicious of two male passengers as they were about to board a flight, according to Steve Coleman, a spokesman for the Port Authority of New York and New Jersey, which runs the airport.

The airline employee tried to confront the men and then pulled a fire alarm, which led to the evacuation around 8:30 p.m., the authorities said. It was not immediately clear what had prompted the flight attendant to be suspicious of the men, who were later questioned by the police and then allowed to board.