MONROEVILLE (KDKA) — Allegheny County Police have launched an investigation into an overnight shooting that killed a young child in Monroeville.

Investigators are trying to better understand how the unsuspecting shooter got their hands on the gun.

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3-year-old Braya Sanders was shot and killed inside her home on Friday night.

Police say they were called to the home along Cambridge Square Drive just after 9:00 p.m.

When Monroeville police arrived at the scene, they found Sanders with a gunshot wound.

After the County’s homicide unit showed up, detectives say they uncovered strong evidence implicating the victim’s older sibling as the shooter.

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Reportedly, the 5-year-old was playing with the unsecured gun when it accidentally went off.

According to police, the gun was legally owned by one of the children’s parents, who is cooperating with the investigation.

Police say that child services have been notified.

On Saturday night, the Allegheny County Medical Examiner ruled Sanders’ death as a homicide.

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Anyone with information related to this case is asked to contact Allegheny County Police at 1-833-ALL-TIPS.