The puppy was left attended in the locked car around 12:30 p.m. at the Quincy Adams station, according to transit police.
The Quincy Fire Department arrived to help open the car door.
It is unclear how long the puppy was trapped in the car.
The temperature plummeted to around 27 degrees at the time the animal was found, according to Weather Underground.
The pup was given to Quincy Animal Control, and it’s unclear what its current condition is at this time.
The owner could face criminal charges after police investigate, authorities said.
It is illegal to leave a pet unattended in a car in extreme heat or cold weather, and the owner could face up to $500 in fines, according to Mass General Law.
No further details about the incident were immediately available.
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