Shocking video shows a child being screamed at while wearing a tire around his neck.

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PASADENA, Calif. (AP) Police will investigate whether a crime occurred at a youth boot camp after videos surfaced showing instructors shouting at a boy wearing a tire around his neck and children being told to drink water until some vomited.

Investigators will question boot camp operator Kelvin "Sgt. Mac" McFarland, police Cmdr. Darryl Qualls told the Pasadena Star-News (http://bit.ly/vtQb7Q ) on Thursday.

"Looking at the video we can only see McFarland, so we will start the investigation with McFarland," Qualls said.

McFarland earlier denied to the newspaper that he appeared in the videos. A call left for him Friday was not immediately returned.

McFarland was charged earlier this year with child abuse, extortion and other crimes.

Prosecutors contend that he handcuffed a truant 14-year-old girl in May and told her family that she would be sent to juvenile detention unless she was enrolled in his camp. She was never enrolled.

The Star-News this week released short video clips it said were made in 2009.

On one, several instructors in military-style fatigues surround and shout at a boy who is wearing a heavy auto tire. At one point, the boy falls down crying but is ordered to stand again.

In the other, several girls and boys are repeatedly ordered to drink water from colored plastic bottles. Several youngsters vomit.

"I would certainly not subject my son or daughter or any child I know to this type of activity," City Council member Victor Gordo told the newspaper.

"The short clips that I reviewed appeared to be more of a situation of intimidation and humiliation appearing to be employed under the guise of physical activity and discipline," Gordo said.

The Star-News said the videos appear to have been made in Pasadena but did not indicate how it obtained them.

McFarland runs Family First Growth Camp in Pasadena, which like other boot camps uses military-style discipline and exercises with a goal of instilling character and keeping at-risk youngsters away from drugs, alcohol and crime.

The camp "doesn't believe in corporal punishment, nor will it be tolerated," according to a camp website.

"The young men/women who come to us are good kids who have begun to make some poor choices with friends, school, drugs, alcohol, attitude with peers and family members," the website said, adding that through the camp, "these kids seek out, find, then learn to love themselves so they can love their families and start to move in a positive direction."

The camp is funded through a combination of fees and charitable donations. Enrollment is through parents, although in some states juvenile justice systems send some offenders to boot camps.

However, some studies have shown that juvenile offenders sent to boot camps were no less likely to commit new crimes than those who were placed in juvenile detention or given probation.

The Star-News did not specify whether the videos were taken at a Family First training session and noted that some children seemed to be wearing T-shirts from another camp.

Keith "Sarge" Gibbs, who runs Sarge's Community Base/Commit II Achieve Boot Camp, said that some of the children appear to be wearing his camp T-shirts.

McFarland worked for him in 2009 but left to form his own camp after Gibbs learned that he had lied about taking a required background check, Gibbs said.

"He left and took 28 families and kids with him, with my shirts and some paperwork," Gibbs told The Associated Press on Friday.

Gibbs said he doubted that the video was shot during one of his camps.

"Those individuals (in the videos) belong to Sgt. McFarland's team. Those are his teammates," he said.