United Flight 1596 was taxiing when the leak occurred. The Port Authority Aircraft Rescue Fire Fighter unit responded and evacuated the plane. A total of 98 passengers were booked onto other flights, the agency said.
A United spokeswoman, Rachael Rivas, said the flight, bound for Las Vegas, experienced a problem with a fuel valve.
"A technical issue on United flight 1596 from Newark to Las Vegas caused a fuel leak prior to departure," Rivas said.
The fuel valve was shut off and the aircraft was moved to a nearby gate where customers safely deplaned and received meal vouchers and access to an amenity cart while we swapped the aircraft. The flight departed later that evening."
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