Fla. Boy, 3, Fatally Shoots Himself with Gun Left in Nightstand While Sister Babysits: Police

His parents had stepped out of the house to go grocery shopping

Tragedy struck Wednesday in Florida when a 3-year-old boy fatally shot himself using a gun he found in his parents' nightstand while his older sister babysat him as his parents went grocery shopping, according to authorities.

Around 6:30 p.m., deputies responded to "one of the worst calls imaginable" in DeLand, the Volusia County Sheriff's Office said. The city is about 35 miles north of Orlando.

At home at the time was the 3-year-old boy and his siblings, a 16-year-old sister and 8-year-old brother. None of their names have been released.

The sister called 9-1-1, screaming "My little brother shot himself!"

In a press conference held Thursday, Sheriff Mike Chitwood said, "What we're assuming is the parents go to Publix and leave the 16-year-old in charge, have probably done it a million and one times. For some reason, and I don't know that we'll ever know that reason, the three-year-old wandered into the bedroom and got into the end table. He picked the gun out and turned it toward himself and shot himself point-blank range."

After CPR was administered by the first deputy on the scene, the little one was pronounced dead at a nearby hospital at 7:03 p.m. local time, Chitwood said.

Sheriff Mike Chitwood. Volusia Sheriff's Office

According to authorities, the father is a state correctional officer, but the weapon — a Canik 9MM firearm — was not government-issued. There was a second firearm in the house that was a Glock stored on top of the refrigerator. There was a safe in the bedroom that was inoperable, Chitwood said.

The investigation is underway. Florida law states that when any minor child is accidentally shot, no arrests shall be made prior to seven days after the shooting, Chitwood said.

PEOPLE reached out to the State Attorney's Office for comment.

Police tape. Getty

"This should never have happened," Chitwood said. "That family shouldn't feel the way they feel. It's heartbreaking to listen to that 9-1-1 call and you're the sister who is calling in. We were all 16 once, did you watch your younger siblings while your parents ran to the store? Yeah! Who would've ever in a million years thought that that would happen?"

He continued, "There is a message here to all parents who own guns, and that message is if you have little ones, even if you have teenagers, you've got to lock them up, man, because you just don't know. Normally what we see is the teenager steals the gun from their parents or their grandparents and then they use it in a crime...I'm going to sound sexist when I say this, but boys have a propensity to be fascinated with firearms....there's no doubt that he found that, and he wanted to play with it."

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As for his message to parents who don't keep their guns locked up, Chitwood said, "I would like them to listen to that 9-1-1 call. The sister says, 'my brother shot himself and he's not breathing.' If you heard that, you would run out right now and buy a gun safe."

Chitwood added, "It's your family's safety. Invest a couple bucks in your family. If you're going to store guns in your house and have kids around, be responsible and get a mechanism that can lock the damn thing up."

For more information on safe firearm storage and the most effective ways to protect children from unsecured firearms, visit BeSMARTforkids.org.