INDIANAPOLIS -- Police on Monday gave the news media surveillance pictures of a person they say shot a 15-year-old boy on an IndyGo bus over the weekend.

A man shot fellow passenger Kevin Gladney on Saturday evening as the public transportation bus was going north on Meridian Street near 14th Street, police said. The bus driver, following protocol, pulled over and opened all doors, and the shooter escaped, according to IndyGo.

Gladney was taken to a hospital, where he was listed in fair condition Monday.

Police said the incident began when someone who had just boarded the bus stepped on a woman's foot as he walked toward the back. Gladney, who was sitting next to the woman, stuck up for her, and the shooting followed, police said.

Police said the shooter used a silver handgun. He was described as black, between 18 and 20 years old, about 5 feet 8 inches tall with a slender build.

Surveillance cameras inside the bus were recording when the shooting happened, police said. In the images released Monday, the man identified by police as the shooter had a beard and a mustache and was wearing a gray hooded sweatshirt, though the hood was not on his head.

Two of the pictures show the man pointing what appears to be a gun.

Police said anyone with information about the shooting should call Crime Stoppers of Central Indiana at 317-262-8477.