Police say a 10-year-old boy who witnessed a stabbing in Brockton alerted authorities, which may have helped save the woman's life.
Brockton police say the stabbing took place just after 7:30 Sunday night at Leslie B. Parmenter Park.
The victim, whose name wasn't released, was airlifted to a Boston hospital with serious injuries.
Two children, who weren't hurt, were taken to a hospital for evaluation.
Witnesses told investigators that they saw four teenagers running away from the crime scene.
Police found a weapon they believe was used in the stabbing, but no arrests had been made as of Monday morning.
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