It was all over a bike.

A teenager is recovering at Children's Hospital of Philadelphia after an unknown male shot him at point-blank range in a brazen South Philadelphia shooting, police said.

About 4:30 p.m., an undercover detective from police's Major Crimes Unit working on an unrelated case saw two men approach a car parked on 20th Street near Morris, Chief Inspector Scott Small said.

One man opened fire on the car, firing eight shots and striking the teenager as he sat in the car's passenger seat.

That victim was hit in the shoulder and leg, and was taken to CHOP, where he remains in stable condition, Small said.

The detective who witnessed the shooting followed the suspect and another male to a home on Mountain Street near 20th, where police set up a barricade involving SWAT and Fire Department personnel.

That home's owner came out and is custody, being interviewed as a person of interest in the shooting, Small said.

He told police that the two men stormed into his home without warning. After clearing the house, SWAT found two handguns hidden in a golf bag inside the home's first floor. No one was inside the home.

Through interviews with the victim and his stepfather, who was driving the vehicle, told investigators that the shooting was fueled by a bike theft yesterday.

But to add insult to injury, the teen shot today was the owner of that stolen bike.

"We're trying to figure out why someone felt the need to shoot a teenager over a stolen bike," Small said.

Police are searching tonight for the two men seen leaving the scene.

Witnesses told police the shooter was a short male between the ages of 17 and 21, Small said.