Investigators say a customer at a Wal-Mart store in Florida fatally shot a man suspected of stealing diapers and wounded a teenage girl.

Orange County Sheriff's Capt. Angelo Nieves said 19-year-old Arthur Adams and two other men left the store in Orlando with two carts of diapers Saturday and were loading the merchandise into a vehicle when a store employee approached them, NBC affiliate WESH reported.

An armed 50-year-old customer heard the commotion and came to the employee's aid.

Nieves says Adams allegedly reached for something in the car and the customer thought he was reaching for a gun and fired his weapon.

The suspects tried to flee the scene but struck two vehicles in the parking lot before ditching their car and running away.

Adams ran to a gas station across the street where he collapsed. He was rushed to the hospital and pronounced dead a short time later, WESH reported. According to Nieves, Adams had a lengthy criminal history that included four felony convictions.

Deputies initially thought the customer only shot Adams but later learned a juvenile girl sitting in the vehicle was also hit in the leg. She fled the scene and went to a hospital hours later. A third suspect is still being sought.

A spokesman for the Orange County Sheriff's office said it's up to the State Attorney's office to decide if the customer who opened fire will face any charges. The customer is cooperating with the investigation, according to WESH.