Jessica Cavallaro, 24, has been charged with murder, two counts of assault and battery with a dangerous weapon causing serious bodily injuries, and illegal possession of a firearm, the Middlesex District Attorney said.
Bedford police received a 911 call around 9 a.m. Thursday that said Cavallaro had told them that she had shot and killed her parents, the prosecutor said.
When police arrived at their parents' home, they found Cavallaro's 56-year-old mother dead inside a car in the front yard, authorities said. Her father, a 56-year-old Bedford man, was also found mortally wounded.
Paramedics rushed him to an area hospital, where he died of his injuries. The parents' names were not released.
Cavallaro was arrested at the scene without incident.
The fatal shooting remains under investigation.
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