An employee at St. Paul's Como Park Senior High School is on leave while police investigate claims of misconduct.
In a letter to families Thursday night, the high school's principal, Theresa Neal, said she wanted to address "an allegation of staff misconduct."
They learned of a possible problem after an internal review, then took it to the St. Paul Police Department who opened up an investigation, the letter says.
She stressed the claims do not involve students, and only said an employee was put on leave back on Dec. 16.
Police got the information on March 8, the Pioneer Press reports.
"I wanted to share with you what I could, however, due to privacy laws and the ongoing police investigation, I am unable to provide additional details about the situation," the letter says.
The employee has not been charged with a crime.