The man who police say shot and killed himself inside a Bucks County sporting goods store over the weekend has been identified.

Mark McCarthy, 58 of Levittown shot himself inside the Dick's Sporting Goods store on Commerce Drive in Fairless Hills.

Customers inside the store say they were stunned.

"Swat team rolled in," said Mike Elwell. "We watched them put together their full suits."

Investigators say the ordeal began around 7:30 p.m. Saturday when McCarthy entered the store and asked to see a shotgun as well as ammunition, according to investigators.

As the clerk was about to hand him the gun, McCarthy allegedly pulled out a handgun, pointed it at the clerk and told him to unlock the shotgun. Police say he then took the shotgun as well as ammo and then barricaded himself inside the store's bathroom.

The entire store, as well as neighboring businesses, was evacuated for four hours as police searched inside, according to authorities.

“We used a robot with cameras to push the door open and a K-9 dog to go inside to make sure it was safe,” said Falls Township Police Department Lt. Henry Ward. “The robot has cameras on it and we were able to see him then.”

Shortly before midnight, police say McCarthy shot and killed himself. The Bucks County Coroner says he died from a single self-inflicted gunshot wound to the chest.

Police say McCarthy was involved in a standoff with Middletown officers in 2002 and was involuntarily committed for mental health treatment in 2010. According to Pennsylvania Law, a person who "has been adjudicated as an incompetent or who has been involuntarily committed to a mental institution for inpatient care and treatment" cannot possess a firearm.