NASHVILLE, Tenn. - A two-year-old girl was accidentally shot and killed by her five-year-old brother with a rifle he received as a birthday gift, Kentucky authorities said on Wednesday.

The shooting occurred on Tuesday afternoon in Burkesville, Kentucky, a community in the south-central part of the state, when the boy was playing with the .22-caliber rifle and accidentally shot his sister in the chest, state police said.

The boy had received the Crickett “youth model” gun for his birthday in November, Cumberland County Coroner Gary White said. White said these guns have child safety locks, but “evidently when the gun was put up, there was a live round in it.”

He said no one realized the gun, which was kept in a corner, was loaded until the fatal gunshot.

White said the children’s mother was home cleaning house at the time of the shooting.

“She had just come out of the kitchen and went to the porch to throw out some grease from the skillet,” White said.

Kentucky State Trooper Billy Gregory said police were investigating and it was “a little early” to talk about possible charges in connection with the shooting.

White called the shooting “a tragic accident.”

“I’ve been the county coroner for 15 years and I think this is the first time I’ve had a case like this,” White said. “I’m hoping that parents will realize that if you have kids, you need to put the guns out of harm’s way.”