PANAMA CITY, Fla. -- The U.S. Justice Department announced Thursday that it has opened an investigation into the death of a 14-year-old boy at a boot camp for juvenile offenders.

The investigation will focus on whether Martin Lee Anderson's rights were violated through use of excessive force or "indifference to serious medical need" by guards at the camp, said U.S. Attorney Gregory R. Miller of Tallahassee.

The probe will include the FBI and the civil rights division of the Justice Department, he said.

Anderson died Jan. 6 at the boot camp after was became uncooperative and was restrained, according to the Bay County sheriff's office. The boy's mother, Gina Jones, contends that her son was murdered by guards who beat him to death.

Law enforcement authorities have resisted legal efforts by news organizations and others to obtain a videotape that two state lawmakers said showed the beating. Civil rights groups, including the NAACP, have called for state and federali investigations into the death.

Bay County officials were scheduled to release autopsy results later Thursday.