A 15-year-old girl has been charged with two counts of capital murder for allegedly killing her sister and mother. 

Deputies were dispatched to the Alabama home after one of the victims called 911 early Wednesday morning, pleading for help, Limestone County Sheriff Mike Blakely told WHNT.

He described the call, which has not been released, as "one of the worst" he has heard in nearly 50 years of law enforcement. 

"You've got two individuals in the process of being murdered, screaming, asking for help and asking the assailant to please stop," Blakely said.

“You could hear the mother actually taking her last breaths and dying there on the phone," he added to WAFF. "What caused this, we don’t know."

Deputies were dispatched to the home, but the mother and daughter had already been stabbed to death. The victims have been identified as Rosa Aminta Maldonado, 44, and her daughter Rosa Lee Maldonado, 19.

The name of the teen suspect has not been released. She was found with self-inflicted wounds and has since been taken to the hospital for treatment, officials said. It's believed she was attempting to commit suicide.

"Whatever explanation is not a reason or justification for something like this," Blakely told WHNT. "I want to know who, what, where, when and how."

He continued: "This is a horrific crime, whether you are 15 or 50 years old. People shouldn't be doing something like this."

A GoFundMe page created by a family member asked for donations for the funeral services for Rosa Aminta and Rosa Lee.

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