ST. PAUL (AP) - A federal judge has dismissed a lawsuit from a Minnesota high school teacher who was body-slammed by a student.

U.S. District Judge David Doty said Thursday that science teacher John Ekblad must instead go through the workers compensation system.

Ekblad was assaulted by a student while trying to break up a fight in the lunchroom at St. Paul Central High School in December 2015. He filed a lawsuit in March against the former superintendent and assistant superintendent of Saint Paul Public Schools, saying they failed to protect him.

The school district says it has already paid Ekblad more than $65,000 in workers compensation and tens of thousands of dollars in medical benefits.

Ekblad's attorney says they plan to appeal.