By CBS3 Staff

PHILADELPHIA (CBS) – A 16-year-old is fighting for his life after he was shot in Philadelphia’s Mayfair section. Police say evidence found at the scene is raising questions about what the teen was up to before he was shot.

The teen was struck in the chest just before 2:30 a.m. Monday on the 3300 block of Longshore Avenue. Police say a ski mask, a gun, and two cell phones were found at the scene.

As officers were on scene investigating, two men told detectives they had just been robbed at gunpoint by someone wearing a ski mask.

“That description matched the 16-year-old who was found shot,” Philadelphia Police Chief Inspector Scott Small said.

Authorities say the robbery victims positively identified the gun, a ski mask and one of two cell phones found just feet away from the teen.

“We just don’t know who shot this 16-year-old,” said Small.

Neighbors say the boy had just moved to the area. An eyewitness says he tried to help the teen.

“I was in my room watching TV and I hear a lot of bangs, like ‘pop, pop, pop,'” recounts eyewitness Marcus Cortes. “He was screaming for help, he was in a lot of pain so my first instinct right away is to hold the pressure on the shot. I had to try to help stop the bleeding.”

The teen was taken to the hospital in critical condition.

Police say they also found a car with a gun in plain view parked near the scene. Police are now looking to determine who the owner of that vehicle is and if it is connected in any way to this shooting.

Investigators are also checking nearby surveillance cameras.

So far, police have not made any arrests.

CBS3’s Crystal Cranmore contributed to this report.