Child Protective Services assigned a special investigator to work with the Brownsville Police Department to conduct a joint investigation in the death of a 15-year-old boy.

The victim’s aunt and her common-law husband were arrested and charged with murder in connection with the death of the nonverbal teen with autism, Brownsville police said.

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Police responded to a home on the 300 block of Center Drive Monday at around 4 a.m. where they found the teen dead at the scene and signs of foul play.

“The scene had some blood, he was laying on a mattress, not fully clothed and there's visible marks on his body,” Brownsville police spokesman Sgt. Billy Killebrew Jr. said. “So they determined at that point to call crime scene to further investigate."

Julie Alexandria Brewington, 27, and her common-law husband, 25-year-old Noe Garza, were arrested and charged with murder. The victim was in Brewington’s custody, police said.

A spokesperson with CPS said there were no prior cases open on anyone involved in this incident —including the boy's biological parents.