A Colorado teacher who worked at a public charter school turned herself in to police this week over a sexual assault against a student that allegedly happened in 2016, police said on Tuesday.

Michelle McMillan, 44, was a teacher at Landmark Academy at the time, when Commerce City police say she sexually assaulted a sixth grader. One of the student's parents reported the alleged assault to police in December 2024.

Commerce City and Brighton police investigators launched an "exhaustive" joint investigation and issued a warrant for McMillan's arrest last week.

She's been charged with sexual assault of a child under 15 by a person in a position of trust, a Class 3 felony. She was released on a $25,000 bond, court records show. She's due in court on Wednesday.

Court records did not show an attorney for McMillan a phone number for her wasn't available through public records.

No other details in the case were immediately available.