TALLAHASSEE, Fla. (AP) — The Florida Department of Law Enforcement is defending its investigation of alleged abuse at a now-defunct Panhandle reform school.

The agency Wednesday responded to questions about why it listed fewer deaths and gravesites in a 2009 report than cited in a recent University of South Florida study.

FDLE officials attributed the lower number to differing requirements for criminal investigations and academic research.

The agency’s investigation was unable to substantiate or refute claims of abuse by former students at the school in Marianna about 60 miles west of Tallahassee.

Criminal investigators identified 85 student deaths and 31 gravesites. The university identified 98 student deaths and 50 gravesites.

FDLE officials said the university study included “probable” and “possible” information that has limited or no value in a criminal investigation.

Copyright 2012 The Associated Press.