HARRIS COUNTY — A heartbreaking tragedy unfolded inside a northwest Harris County apartment Thursday night when a 4-year-old girl found her own mother’s gun hidden inside a closet — and accidentally pulled the trigger.

In a matter of seconds, the little girl’s life ended.

The child was alone inside the closet when investigators say she discovered the firearm. She was shot and rushed to a hospital, but the 4-year-old could not be saved.

She died from her injuries, leaving behind a devastated family and a haunting question for investigators: How did a gun belonging to her mother end up within the reach of a child so young?

Harris County Sheriff’s Office Precinct 4 deputies were called to a Champions-area apartment complex near FM 1960 at about 11 p.m.

The girl’s mother and her 10-year-old sibling were home at the time, investigators said.

Authorities say the gun belonged to the child’s mother, who told investigators she had stored it inside the closet.

“The firearm does belong to the mother. She owned the firearm, and she indicated it was inside the closet. That’s where it was stored at,” HCSO Sgt. Jason Brown said. “That’s how the child ended up finding it.”

Brown said the weapon does not appear to have been secured.

Investigators are now trying to reconstruct the heartbreaking chain of events that ended with a 4-year-old child fatally shooting herself.

“We are in the process of interviewing the mother and the 10-year-old child who was home at the time, trying to determine exactly how the child got in the closet — you know, how this happened, as far as how the child found the firearm. But as of right now, we believe it’s going to be accidental,” Brown said.

The investigation is continuing, and authorities have not ruled out criminal charges against the mother.

Brown said charges are possible as investigators determine how the firearm was stored and how the child was able to get to it.

For a family that began Thursday night with a mother, her two children and a gun stored inside a closet, the night ended with the unimaginable loss of a 4-year-old girl.