Investigators have determined the cause of a fire that damaged Bunger Middle School in Evansdale on Wednesday (October 22, 2014).

According to Evansdale Police and Fire Chief Kent Smock, someone intentionally set the fire in a girl's bathroom on the north side of the building. He said police are investigating the fire as a case of arson. No arrests have been made, but investigators are talking with several witnesses.

The fire caused extensive damage to the bathroom and was contained to that area, but nearly half of the school received extensive smoke damage. Damage to the rest of the structure was described as minor to moderate.

When firefighters arrived at the scene around 10 a.m. Wednesday, smoke inside the school was so thick they had a hard time pin-pointing the source of the fire.

Bunger's nearly 400 students and 50 faculty members were evacuated to nearby Prince of Peace Lutheran Church. Because of the smoke damage, classes were cancelled for the day at 11 a.m. Wednesday.

No classes were held at Bunger on Thursday or Friday this week, due to parent-teacher conference. Waterloo school officials expect classes to resume, as scheduled, on Monday.