A California middle school teacher was taken into custody Wednesday after she was found to be in a sexual relationship with a 15-year-old girl.

40-year-old Heather Amanda Butts, a teacher at Taylor Middle School, who taught drama and English, was apprehended on suspicion of lewd and lascivious acts involving a child, and contacting or communicating with a minor with knowledge and intent to commit specified offenses.

It isn’t clear whether or not the girl was a student.

The San Bruno police learned of the relationship after a caller notified them at around 5:40 p.m. Monday that the middle-aged teacher was “engaged in inappropriate behavior” inside a vehicle parked a street in San Bruno.

When officers arrived, they found her in the vehicle with the teen girl. they later determined that she and the girl had been in a sexual relationship.

A warrant for her arrest was issued on Tuesday and she was arrested at her home on Wednesday.

Anyone with more information on the case can anonymously call police at (650) 616-7100 or email [email protected].