SAN ANTONIO (CBSDFW.COM/CNN) – Tragedy at a Memorial Day barbecue in Texas after a 4-year-old was shot and killed.

The shooting in San Antonio is still under investigation, but appears to be accidental.

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“We’re not sure at this point who was holding the gun when it went off and the four-year-old was shot in the stomach,” said SAPD Chief William McManus.

San Antonio police say while adults inside and in the backyard of the home were enjoying a barbecue, a 10-year-old and 4-year-old boy were alone, playing inside a bedroom.

Chief McManus says that is when the boys got their hands on a weapon. “Someone heard a pop, they ran in and found a little boy,” he said.

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While the family immediately called for an ambulance, they tried rushing the boy to the hospital themselves. Along the way, they were able to flag down the ambulance in route, which then took the child to a local hospital but he died from his injuries.

“I don’t know where the gun was stored. I don’t know where the little boys found it… it may well have been secured, but apparently not well enough,” the Chief said.

The incident is still under investigation to determine if charges will be filed.

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