(NewsNation) — A mother whose daughter was kidnapped and murdered by a Mexican drug cartel spent years hunting down her child’s captors in a dangerous — and ultimately fatal — mission.

Miriam Elizabeth Rodríguez Martínez’s daughter, Karen Rodríguez, was abducted in the northeastern Mexico city of San Fernando, Tamaulipas, on January 23, 2012, after a group of armed men from the Los Zetas cartel forced their way into her car and took off with her inside.  

Her captors demanded thousands of dollars in ransom payments in exchange for her return. However, in 2014, despite the family’s compliance, Karen was murdered, and her remains were found on an abandoned ranch.

Following Karen’s death, her mother worked at night to find out exactly what happened to her.

Using disguises, a fake handgun and false identification, Rodríguez managed to locate and interrogate several members of the Los Zetas cartel, the Daily Mail reports, one of the most dangerous and violent in the country. 

The New York Times reported one of her targets was a young florist who she’d chased for years and tracked down online after learning the man sold flowers on the street before joining the cartel.

Rodríguez was responsible for taking down at least ten criminals during her unrelenting pursuit before she was murdered outside her home in 2017.