Boston Police are investigating after a person was stabbed in the city's Roxbury neighborhood Wednesday night.
Police responded to an apartment complex on Highland Street, where the victim was found with life-threatening injuries.
Authorities believe they know who the suspect is, saying that the incident was not random.
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Police were investigating as children were out trick-or-treating.
"It's really sad. And it's super disappointing, especially cause people take advantage of times like this, and days like this, because they think that they can just get away with it," said Morgan Taylor, who was visiting her friend. "There's no point in violence, especially on a day when we're supposed to be celebrating. Kids are out."
Part of the neighborhood was sealed off to neighbors as a K-9 team was brought in to search for evidence.
Detectives taped off a black BMW. Investigators said it was a part of the investigation, but they did not say how it was connected.