A first-grade teacher in Maryland was arrested when police found out she was allegedly abusing her students during school hours.

Susan Lee Burke, 35, a teacher at Greencastle Elementary School, is facing nine counts of second-degree assault from December incidents, according to NBC Washington.

An investigation started after one student filed a complaint to Montgomery County police claiming physical assaults on several occasions. Though interviews, police learned that eight other students were reportedly kicked, scratched, punched and choked by Burke. All the victims were ages 6 or 7, and some said they witnessed the attacks.

Burke had been with the Montgomery County School District for 10 years, but was placed on administrative leave after the first complaint.

Click here to read more on this alleged classroom abuse at NBC Washington.