Brownsville police arrested a third individual in connection with the death of a 15-year-old boy with autism. 

Rebecca Garza was arrested Tuesday on a charge of failure to report a felony.

According to Brownsville police, Rebecca Garza is the mother of Noe Garza — the common law husband of the teen’s aunt.

Noe Garza and Julie Brewington were charged last week with murder in connection with the teen’s death.

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Police responded to a home on the 300 block of Center Drive where they found the teen dead at the scene and signs of foul play. The victim was in Brewington’s custody, police said.

“The child is not theirs, that is right now what the detectives are trying to piece together as to how is it the child got there in the first place,” Brownsville police Investigator Martin Sandoval said. “They've been trying to locate the parents. It's kind of very difficult because the child was autistic nonverbal. We haven't found any records of him in any of our schools, so it's making it difficult."

Results of a full autopsy report are still pending, Sandoval added.

Police said the suspects are not cooperating with police regarding where the boy’s parents are.