A team of University of South Florida anthropologists and archaeologists have found at least 19 more graves at the former Arthur G. Dozier School for Boys in Marianna, Fla., than has been officially reported.

Once the largest reform school in the nation, the century-old institution has been the subject of numerous investigations into abuse allegations and suspicious deaths of children held there.

The USF research team led by Erin Kimmerle, Richard Estabrook, Christian Wells, and Antoinette Jackson released its interim findings Monday as it delivered to state officials a lengthy report detailing the number and location of graves at the school’s Boot Hill Cemetery and surrounding wooded area.