(Newser) – A Mexican woman who spent two years fighting to bring her daughter's killer to justice was herself shot to death on Thursday, possibly by the same man suspected of murdering the teen. The crime was caught by a security camera, which shows masked men pulling up to anti-crime crusader Marisela Escobedo Ortiz outside the governor's office in the northern city of Chihuahua, where she was holding a vigil. One appeared to speak with her before she started running across the street; the gunman chased after her and shot her in the head, reports the AP.

In Ciudad Juarez, where Escobedo's 17-year-old daughter's burned and dismembered remains were found in a trash can in 2009, people gathered outside the state prosecutors office with signs demanding "Justice for Marisela." The man suspected of killing the teen—her live-in boyfriend, Sergio Barraza—was released in April after three judges cited a lack of evidence. The judges were suspended for that sentence, and Barraza is now a chief suspect in Escobedo's death, says the attorney general's office. Click for more on Escobedo's crusade to "not allow one more young woman to be killed in this city."