Officers grabbed 25-year-old Khajah Gaye after he manipulated the turnstile at the Journal Square PATH station in Jersey City around 5 p.m., the authority's Joseph Pentangelo said.
Gaye, who Pentangelo said didn't have identification, was arrested.
Officers found the knife inside the pack -- which Pentangelo said he told them was "for pigs like you."
Gaye was charged with two weapons possession counts and theft of services and released, pending a court hearing, under New Jersey's 2017 bail reform law.
"There were no injuries and no disruption to transportation," Pentangelo said.
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