Updated

Dallas police are investigating the murder of a 17-year-old girl whose body was found in a creek Sunday morning.

Mikayla Mitchell’s body was floating in a creek at Blair Park in South Dallas. A family friend said investigators told Mikayla's family that the teen had been tortured and dismembered.

Sunshine Grigg told Fox 4 News that Mikayla had recently started hanging around some boys Grigg described as "bad news" and had run away the week before her death.

"Her mom went and picked her up in Abilene, and then she came home for a week," Grigg said. "And then she came home again with these boys and left town with them. And now we're never going to see her again."

Mikayla's stepfather, Dr. Howard Gregg Diamond, was recently arrested on federal drug conspiracy charges related to seven overdose deaths. Diamond is accused of running a pill mill that distributed powerful pain medications to patients who didn't really need them.

Mikayla's relatives claim that her death has nothing to do with her stepfather's case. Police have yet to identify any suspects.

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