The Bucks County District Attorney's Office is investigating the alleged assault of a teen boy by police officers.

The mother of the 14-year-old boy, who was arrested for shoplifting, is accusing police of roughing him up.

Editor's Note: A warning that this story contains graphic images.

"The picture speaks a thousand words," says Marissa Sargeant, who shared several graphic photos with NBC10 that shows her son bruised, cut and swollen.

The teen was arrested by Tullytown Police for retail theft at Walmart on Tuesday night, along with an adult relative.

"What he did was wrong. He was coerced by a 19-year-old. He does know better," said Sargeant.



The teen and his 19-year-old cousin Jordan Gibson were both positively identified by Wal-Mart Asset Protection.



Authorities say after the teen's arrest, and before he was loaded into a police car, he took off running along Route 13 while handcuffed.



Bucks County District Attorney David Heckler tells NBC10 that police officers yelled warnings at the teen and fearing for his safety, they fired a stun gun to subdue him. The D.A. says the Taser struck the boy in the face and with his hands cuffed, the boy had no way to brace himself against falling face-first.



"That doesn't sound right. There's no way, if he was running from behind, that he would get hit with a taser in the front of his face," said Sargeant.



Sargeant says the officers must have hit or kicked her son, and then told him not to tell anyone. The boy was taken directly to the hospital for treatment.



Police aren't offering up anymore information because of the family's threat of a lawsuit.



"I just want some justice. I even pray for the police officers because they need help," said Sargeant.



While Heckler doesn't believe there was any wrongdoing from police, he says his office is now investigating the incident after a request from the Tullytown Police Chief.

Meanwhile, the boy's family hired Center City attorney Fortunato Perri Jr. who plans to file a complaint. Perri Jr. says he spoke briefly with the boy.

"We intend to develop the facts and circumstances a bit further," Perri said. "But just simply with the nature of the injuries that occurred in this case, I think it's clear that the police used excessive force. That's what we're investigating at this point."