The Pima County Sheriff's Office in Arizona will conduct an internal investigation after a deputy was caught on cellphone video tackling a 15-year-old boy with no arms or legs, an incident that the local public defender calls "unconscionable and horrific."

The eight-minute video, first reported by local station KOLD, shows the boy yelling as the sheriff's deputy pins him to a kitchen floor inside a Tucson group home, restraining the quadruple amputee. The incident was recorded by another boy at the group home whose head was later pushed into a wall.

"These are boys who are already traumatized. That's why they're in a group home. These are children who society has discarded and left behind," said Pima County Public Defender Joel Feinman, who is representing both boys and withholding most information about them to protect their privacy.

"For them to be assaulted by an armed deputy with a badge and a gun, the personification of the very organization that is meant to protect and serve them, is absolutely terrible," Feinman said in a phone interview Friday.

The deputy, Manuel Van Santen, has been placed on administrative leave while the investigation proceeds, the sheriff's office said in a statement Friday afternoon.

The incident took place on Sept. 26 after an employee at the group home called law enforcement to report that the 15-year-old, Immanuel, had knocked over a trash can. Feinman said Immanuel, who is in state custody because he was abandoned by his family, was upset over a recent school suspension.

Van Santen apparently found that Immanuel was disturbing the peace and restrained him, according to Feinman. C.J., a 16-year-old who lives in the home, then started recording the incident from a nearby room while he ate a bowl of cereal, Feinman said.

The video shows the deputy crouching on the floor and putting a headlock around a shirtless Immanuel. The boy becomes agitated, loudly pleading with the officer to let him go. The deputy seems to loosen his grip, and Immanuel tries to get away.

That's when the law enforcement officer tackles him, bringing him to the floor by a refrigerator and pressing down with his body weight. The boy can be heard yelling. Van Santen eventually allows Immanuel to get up, and he asks the boy if he has a problem.

The boy responds that he does not have a problem. But after a brief back-and-forth, Van Santen raises his voice and appears to become angry. The deputy shouts: "I will raise my voice to you whenever the [expletive] I want, you understand?"

C.J. then interjects: "Hey, you asked him a question, and he answered!" The deputy yells back at C.J.: "Shut the hell up!"

The officer orders the 16-year-old to go back to his room, but the boy responds that he is finishing his cereal and isn't allowed to eat in his room.

Van Santen approaches C.J., orders him to stay out of the situation and again tells him to "shut the hell up." The boy tells the officer to "get the [expletive] out of my face." The deputy later says: "You're going to get arrested, too."

Later in the video, another person in the room appears to take over the cellphone recording as C.J. is handcuffed and slammed into a wall by the deputy.

Feinman said Immanuel and C.J. were arrested for disorderly conduct and taken to juvenile detention. Immanuel was originally charged with disorderly conduct, but that case has since been dismissed, according to Feinman.

"I'd like people to imagine that this is their child," Feinman said.