Dozens of state and federal investigators are looking into child abuse allegations at a privately-owned boarding school for troubled teens in southeastern Iowa.

Agents descended on the Midwest Academy campus in Keokuk to serve a search warrant Thursday and Friday, interviewing students and employees. They served a second warrant at a related building, the Midwest Treatment Center, in Montrose.

The Division of Criminal Investigation said the warrants stemmed from a complaint alleging that a staff member of Midwest Academy sexually assaulted a resident. The Iowa Department of Human Services and the FBI are also investigating.

A former employee claims in a lawsuit that she was fired in December, one day after reporting to DHS that a female student had been sexually abused by a staff member.

Academy officials declined comment.