COLE COUNTY (AP) -- A Cole County woman who assaulted an elementary teacher was sentenced to four years in prison.

Thirty-five-year-old Joann Rutherford was sentenced Wednesday for felony assault on school property.

She was arrested after hitting a teacher at Pioneer Trail Elementary School in Apache Flats last March.

The Jefferson City News-Tribune reports Rutherford went to the school to contact her son. Rutherford's custody of the boy had been temporarily suspended and staff tried to stop her from seeing the boy.

Prosecutors say Rutherford hit a teacher and grabbed her son but was prevented from taking him out of the building. The school was briefly locked down until Rutherford left.

The teacher was not seriously injured.

According to court records Rutherford pleaded guilty in October 2012 to the felony charge of assault while on school property.

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