The bear was first spotted about a mile away from the school around noon, Tuesday and police had been following it before it entered the school.
The school's secretary saw it run into the school through security cameras sometime before 1 p.m., then alerted Father Joe Kempf and the handful of other people who were in the school. Classes were not in session so no students were in the building.
Kempf told KMOX as of 2:45 p.m. the bear was still inside the school and was stuck in the boys bathroom. Eureka police Capt. David Wilson says the bear had been spotted around Main Street earlier in the day and there have been no reports of injuries.
He advised anyone to just let the bear be and expects it to return to the woods soon.
Tom Meister, bear expert with Missouri Department of Conservation said the bear may have smelled food and that's why it wandered into the building.
Eureka Police and Missouri Conversation employees were on the scene.
There are multiple posts on the Eureka communtity Facebook page about a bear that was in the area, Monday.