A 9-month-old baby is dead after his older brother, age 5, accidentally shot him at their rural Missouri home on Monday.

The baby was in a playpen when his older brother found the loaded gun lying on a bed and apparently discharged the weapon, Nodaway County Sheriff Darren White told KCTV.

Alexis Widerholt, the boys' mother, called police at around 9 a.m. Monday saying her 5-year-old son shot her baby with a paintball gun, the Nodaway County Sheriff's Office said.

"I just happened to be standing by and answered the phone," White told KETV. "The lady on the other end was very frantic and said that she needed an ambulance at her home."

But when emergency responders arrived at the home in Elmo, Missouri, it was determined the infant was shot with a .22-caliber magnum revolver.

Doctors at Children's Mercy's Hospital tried saving the child but he later died, KCTV reported.

Police do not suspect foul play was involved. But they are looking into the owner of the gun, which belonged to another relative and not the mother, the sheriff's office told the station.

"We are big supporters of firearms around here," White told KETV. "We live in a rural area. We have a lot of people who own weapons. They hunt. They shoot.  Most people are very safe with them, and this is one of those cases where everything went together in the wrong way."