RUSTON, La. (AP) — Fire investigators in Ruston believe a weekend fire that gutted a Louisiana Tech University fraternity house originated in the fireplace while students burned old class notes to celebrate the end of their school year.

Saturday afternoon, students noticed smoke coming from the ceiling area above the fireplace and originally believed it was a chimney fire. They tried to put out the fire using a garden hose from the rooftop. The Times of Shreveport that investigators believe an hour passed before 911 was called, which could have allowed the flames to spread undetected throughout the walls of the structure.

There were no serious injuries in the blaze but three firefighters were treated and released at a hospital. Ruston Fire Department spokesman Eric Brazzel said the $1 million building was a total loss.