The 17-year-old robber tried carjacking the driver at gunpoint on 3rd Street but ended up taking the keys and running, Lt. Fred Pulice said.
The driver, afraid that he'd return, immediately called police, the lieutenant said.
Officers were interviewing him when the teen came around the corner, apparently to collect the car, Pulice said.
They chased him on foot before catching the youth in Mackay Park. He apparently was carrying the keys to the car that police said he intended to steal.
Police detained the juvenile and issued him delinquency complaints for robbery, attempted carjacking and illegal weapons possession.
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