Chasity Nunez and her daughter Zella Nunez were shot and killed inside their car in the area of Lisbon Street at Englewood Avenue around 3 p.m. Chasity leaves behind a 2-year-old daughter named Isla, reports said.
Photos of the car show multiple bullet holes in the driver's side window.
Karel Mangual, 28, was arrested and charged with armed assault to murder and carrying a firearm without a license. Police were searching for 27-year-old Dejan Belnavis in connection with the killing.
Mangual was ordered held without bail.
Police did not release a motive for the killing.
Chasity Nunez was a Brooklyn native who worked at MIT Healthcare Innovation as a patient safety and clinical quality coordinator, according to her LinkedIn. Her mother told the Daily Mail that Chasity had earned two master's degrees from Worcester State University.
"She was a professional. She wasn't out there like that. She was a hard worker supporting her daughters," Noemi Nunez told the news outlet.
Worcester Public School Communications Officer Dan O'Brien told ABC News that Zella was a "high-achieve sixth grader" who was liked by her teachers and had many friends.
Detectives ask anyone with information on Belnavis' whereabouts is asked to call investigators at 508-799-8651.
Belnavis should be considered armed and dangerous, police said.
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