5-year-old fatally shoots 16-month-old brother at Indiana apartment

A 16-month-old boy was fatally shot by his 5-year-old sibling Tuesday at a northwestern Indiana apartment, authorities said.

The shooting killed Isiah Johnson, Tippecanoe County Coroner Carrie Costello said.

"Detectives with the Lafayette Police Department determined that the child was shot by his five-year-old sibling, who was able to gain access to a weapon in the apartment," police said in a news release Tuesday.

Police respond to a shooting at a home in Lafayette, Ind., on Tuesday. WHTR

The shooting at the Romney Meadows apartment complex in Lafayette was reported around 3 p.m., Lafayette Police Lt. Matt Gard said.

A call of a child not breathing did not come from someone inside the apartment at the time the shot was fired, and no resuscitation was performed by first responders at the scene, he said.

The child was found dead from the gunshot wound inside the apartment, according to the news release.

“There was one adult and two children inside the apartment,” Gard said. All three have been interviewed by investigators.

No arrests have been made, he said.

The preliminary cause of death was a gunshot wound, the coroner’s office announced Wednesday afternoon. The manner of death was listed as pending until the investigation is completed and toxicology results have returned.

Capt. Brian Phillips of the Lafayette Police Department declined to answer questions from NBC News about who called police, where the gun was stored, whether it was purchased legally or whether any adults are facing charges.

"This is an ongoing investigation, and we have no additional information to release at this time," he said.