INDIANAPOLIS — Police are investigating a quadruple shooting that left one person dead in the parking lot of a Steak ‘n Shake restaurant on the south side of Indianapolis.

According to the Indianapolis Metropolitan Police Department, just after 11 p.m. Thursday night, they were called to the 4000 block of the South East Street. When they arrived, they found four men shot.

Three of the men were found awake and breathing inside the Steak ‘n Shake and were transported to a local hospital in stable condition.

The fourth man was found unresponsive in the parking lot. He was pronounced dead at the scene. The Marion County Coroner’s Office identified him as 21-year-old Artemas Boyd II.

“We do not believe that the Steak ‘n Shake business is associated in any way with the shooting other than the individuals were in the parking lot,” said IMPD Major Mike Leepper. “The three individuals that sustained gunshot wounds that are still alive ran inside the business for help.”

One of the witnesses to the shooting said he was scared for his life.

“I am sitting in my truck, and all of a sudden, I am hearing bam, bam, bam, bam,” said Robert Bobb.

Police said they believe all four people shot are to be in their 20s.

“All these individuals are young men,” said Leepper. “This is just not acceptable. We have to explain to a family tonight why their loved one was shot and killed in a Steak ‘n Shake parking lot.”

Police have not yet released any details of what led up to the shooting or whether they have a suspect. They recovered at least four guns from the scene.

“Our agency will not stand for this. Our agency will do everything in their power to bring whoever is involved in this justice,” said Leepper.

And for Bobb, this hits close to home as his youngest son is the same age as the young man killed Thursday night.

“That could’ve been my child,” said Bobb. “I feel sorry for his parents.”

Anyone with information is asked to call Crime Stoppers at 317-262-8477 or (TIPS).

Hannah Follman contributed to this story.