A 14-year-old boy kicked and punched by guards at a juvenile boot camp died because the sheriff's officials suffocated him, a medical examiner said Friday, contradicting a colleague who blamed the death on a usually benign blood disorder.

"Martin Anderson's death was caused by suffocation due to actions of the guards at the boot camp," said Dr. Vernard Adams, who conducted the second autopsy.

Adams said the suffocation was caused by hands blocking the boy's mouth, as well as the "forced inhalation of ammonia fumes" that caused his vocal cords to spasm, blocking his upper airway.

The autopsy report draws no conclusions about whether Anderson's death was a homicide or an accident.

Martin Lee Anderson's body was exhumed after a camp surveillance videotape surfaced showing the guards roughing him up and shoving ammonia pills up his nose Jan. 5, a day before he died. His family had questioned the initial finding by Dr. Charles Siebert, the Bay County Medical Examiner, that the boy died of complications of sickle cell trait.

"I am disturbed by Dr. Adams' findings and consider the actions of the Bay County boot camp guards deplorable," said Gov. Jeb Bush, who ordered the investigation that led to the second autopsy.

In a statement, Bush assured Anderson's parents that the state will provide any resources prosecutors deem necessary "to complete this investigation as quickly as possible."

No one has been arrested in connection with the death, which sparked protests at the state Capitol, forced lawmakers to scrap the military-style camps and led to the resignation of the state's top law enforcement officer.

Anderson's parents planned a news conference Friday evening at their attorney's Tallahassee office to respond to the findings. Marc Tochterman, a spokesman for the Bay County Sheriff's Office, which operated the boot camp, said the agency had no immediate comment.

Siebert said Friday that he stands by his findings. If Anderson had suffocated, he said, there would have been higher levels of carbon dioxide in the boy's body.

"I came to my conclusion by valid means," Siebert said. "I've seen no explanation as to how (Adams) came to his conclusion."

State Attorney General Charlie Crist said Friday that Siebert "should probably be suspended pending further review." He said the second autopsy report wasn't surprising.

"I can't say I'm shocked after having watched the tape. What was surprising was the first autopsy," Crist said. He said there will "probably will be arrests."

The videotape shows Anderson being kneed, struck and dragged by guards on his first day at the Bay County Sheriff's boot camp for juvenile offenders. He was eventually taken to a Pensacola hospital, where he died a few hours later.

Waylon Graham, attorney for sheriff's Lt. Charles Helms, who was second in command of the boot camp and present in the exercise yard that day, said he wasn't shocked by Adams' report. Graham said the investigation has turned into a "witch hunt" with criminal charges inevitable.

"I think (Helms) knows what's coming next," Graham said. "When you get an autopsy with results like that it's pretty clear that they are going to charge him and obviously the others. It would take a pretty naive person to think otherwise."

He said Helms doesn't believe that the guards caused Anderson's death.

The second autopsy was ordered by Hillsborough County State Attorney Mark Ober, whom Bush tapped to lead the investigation.

A forensic pathologist hired by Anderson's family observed the second autopsy, Dr. Michael Baden, said afterward that he believed Anderson didn't die from natural causes.

Siebert's autopsy concluded that physical exertion had triggered sickle cell trait and ultimately caused small blood clots to develop in Anderson's bloodstream, which resulted in internal bleeding.

Anderson had collapsed while doing push-ups, sit-ups, running laps and other exercises that were part of his admission process at the camp. The sheriff's office said force was used on Anderson because he was uncooperative.

He had been sent to the boot camp for violating probation by trespassing at a school after he and his cousins were charged with stealing their grandmother's car from a church parking lot.