FARIBAULT, Minn. (WCCO) — Police are investigating alleged sex abuse by two more employees at a Minnesota boarding school.

That now makes four men who are accused of child sex abuse while working at Shattuck-St. Mary’s in Faribault. Prosecutors charged former teacher Joseph Machlitt on Wednesday with abusing a 14-year-old student back in 1980. Investigators say an arrest last month led to the latest investigation.

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Police say they are investigating Machlitt, 63, of St. Paul after a former student said he was involved in sexual activity with the former art and photography teacher back in 1980.

The criminal complaint says Machlitt was supervising a student who hit his head in the swimming pool. The student was waiting in the dorm, and woke up to find Machlitt massaging his legs, the criminal complaint says.

Machlitt then allegedly engaged in sexual activity with the student, who was then 14 years old. Investigators say the victim reported one additional incident of inappropriate activity.

“Police believe that at the time of the incidents, Shattuck-St. Mary’s administrators and staff were not aware of the sexual abuse,” Faribault Police Department spokesperson Don Gudmunson said.

After the victim came forward, Faribault Police and the Bureau of Criminal Apprehension (BCA) worked to locate Machlitt. Cpt. Neal Pederson said Machlitt was interviewed by BCA agents and at first didn’t admit to what the victim was accusing him of.

“But then he came back in two days later and then admitted to that action,” Pederson said.

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The victim initially came forward after hearing earlier reports of Shattuck-St. Mary’s teachers being accused of sexual misconduct with students, police said.

Machlitt has been charged with one count each of third- and one fourth-degree criminal sexual conduct.

Shattuck-St. Mary’s spokesperson, Jon Austin, issued a statement Wednesday afternoon, reading:

“Like anyone, we’re appalled by the alleged actions, which the school learned of for the first time today, involving a former employee who left the school in 1980. The behavior described in the complaint is offensive, wrong and violates our code of conduct. We will continue to work with the Faribault Police Department to assist in their investigation and we encourage anyone with information about such matters to come forward.”

In October, WCCO reported about the 17 sex abuse charges filed against former drama teacher Lynn Seibel of Shattuck-St. Mary’s. (Seibel is currently in Los Angeles, police say. It is not known when he will be brought back to Minnesota.) Not long after the Seibel case, another teacher — Len Jones — was accused of having a relationship with a foreign-exchange student that began when she was just 15 years old.

Police said late Wednesday that they are also looking into a fourth employee who allegedly abused a student between 1980 and 1992.

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They say it’s early in the investigation, and that the worker no longer lives in Minnesota.