Guards Patrick Garrett, Henry Dickens, Charles Enfinger, Henry McFadden, Raymond Hauck and Joseph Walsh had frequent physical altercations with detainees, according to the Bay County Sheriff's Office Boot Camp documents, obtained by The Associated Press.

Each of the men was involved in the confrontation with Martin Lee Anderson on Jan. 5.

Anderson died the next morning. Prosecutors said following a second autopsy this week that the teen did not die of natural causes. The boy's family, Florida's black legislative leaders and the NAACP have called for the guards' arrests.

Late Thursday, the medical examiner for Bay County who did the original autopsy on Anderson issued a statement defending his finding that Anderson died a natural death from sickle cell trait, a usually benign blood disorder many blacks have.

"My conclusion, based on more than a decade of practice, is that the exertion from exercise triggered Mr. Anderson's sickle cell trait which caused Disseminated Intravascular Coagulation (DIC), resulting in hemorrhaging," Dr. Charles Siebert said.

Siebert observed a second autopsy done Monday by Hillsborough County Medical Examiner Dr. Vernard Adams. Hillsborough State Attorney Mark Ober took over the case and requested the second autopsy after the state attorney for Bay County stepped down citing close ties with law enforcement.

The five guards shown on tape in the Anderson case, were involved in at least 63 other instances using knee strikes, hammer-fist blows, painful pressure point restraints and other physical encounters with detainees, according to Florida Department of Juvenile Justice Protective Action Responsive Reports filed in 2004 and 2005.

Garrett, who has worked at the camp five years, wrote the report about the Anderson case. He said Enfinger and Walsh "restrained" the boy against a fence after he refused to run laps.

"I ordered offender Anderson to stop resisting and relax his arms. When (he) refused to comply with those instructions, I applied a knee strike to his left thigh and escorted him to the ground," Garrett wrote. "After reaching the ground, I applied a bent wrist to Offender Anderson's left wrist for approximately 7 seconds."

Surveillance video shows the guards dragging a limp Anderson as they repeatedly hit and kicked him.

The report of the 30-minute ordeal also details actions by guard Henry Dickens, 59, a 10-year boot camp veteran, who poured water on Anderson and later applied a pressure point to his head. Pressure points to the head were banned by the state in 2004.

Garrett said officers continued to "counsel" Anderson by applying knee strikes, pressure point blows and bending his wrists backward until he "stopped responding."

Daniel Mears, a Florida State University criminology professor, said he is not surprised by the culture of physical confrontation at the camp.

"With a boot camp, it's pure power almost 24-7. We tell you when to get up and if you don't, you are doing push ups. There is no question there can be a different culture that occurs in boot camps that allows for more violence than is needed to occur," Mears said.

Gov. Jeb Bush on Thursday defended the state's boot camp system, noting the number of kids going into the adult system has dropped 42 percent during his tenure as governor.

"It's up to the Legislature if they want to close boot camps," Bush said. "This tragic case is something that we need to look at, investigate, prosecute if appropriate ... but it doesn't mean that we should get rid of a policy that has yielded a good result."

The Bay County camp no longer houses any juvenile and is being closed. Florida has closed a number of its boot camps in recent years.

One incident chronicled in the Bay County records involved Dickens and other guards who responded to a June 2 suicide attempt.

A guard wrote that he discovered a youth lying on his foot locker with a bed sheet around his neck.

The guards immediately began to restrain the boy, using pressure points to subdue him, and knocking him to the floor.

In a July 2002 report, Garrett described restraining a youth on the exercise field and using knee strikes and pressure points similar to those used on Anderson.

In March 2005, Garrett and drill instructor Henry McFadden, who was also involved in the Anderson case, restrained another boy in the exercise yard, applying "a bent wrist to his right wrist for approximately 7 to 9 seconds," Garrett wrote in his report.

Another March 2005 report reveals details of Dickens, Enfinger and another guard using the pressure point procedures on a different youth in the exercise yard.

Mears likened the guards' actions to those of soldiers at war.

"Working with juvenile offenders is hard. They aren't going to be nice and they are going to be physically confrontative. It's a whole different world than working at your desk," Mears said. "You always have this risk of becoming violent and abusive."

Each of the guards involved in the Anderson case was placed on administrative duties out of direct contact with juveniles after Anderson's death.

On Jan. 27, Hauck was placed on disciplinary probation for a year following a three-day suspension without pay on Jan. 30, Feb. 1 and Feb. 8. His personnel file does not specify the reason for Hauck's suspension or probation.