NEWARK — The monorail at Newark Liberty International Airport has resumed service after being down for two hours, causing a backlog for holiday travelers.

The AirTrain connects the main terminals with parking lots and a New Jersey Transit rail station. It stopped at about 3:20 p.m. Friday due to equipment problems and resumed service at 5:20 p.m.

Shuttle buses were still being used to take travelers to the terminals.

The monorail started operation 20 years ago. Last year the Port Authority of New York and New Jersey, which operates the AirTrain and the airport, announced it has to be replaced because it won't be safe for passengers to ride by 2022.

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