HOUSTON (KIAH) — An elderly man was shot and killed by a group of teenagers on Monday night, Houston police said.

Police said that they responded to a report of a shooting at a Walmart on E. Crosstimbers and Fulton around 8:45 p.m. Monday to find a man with gunshot wounds. He was later taken to a hospital where he was pronounced dead.

Investigators said that the man was walking down the street when he was approached by a group of four teenage girls and two teenage boys, who began harassing the man.

The man then began swinging his cane to defend himself before one of the boys turned around and fired one shot, hitting the man in the chest.

Police said that two of the suspects fled the scene by getting on a METRORail train.

There was no motive for the shooting, but a witness is cooperating with police.