An overheated battery from a vape pen sparked a fire in Muir Hall Wednesday night, San Luis Obispo firefighters on the scene told Mustang News.

The San Luis Obispo Fire Department and Cal Poly Police were on the scene. SLOFD had four fire units and the battalion fire chief dispatched to the fire around 9:18 p.m. until 10:30 p.m.

SLOFD’s incident commander, Alec Flatos, said the damage was contained mostly to the bed and bedding material.

Students in the red-brick building were evacuated for about an hour, donning their pajamas and blankets in the 45-degree weather.

Flatos said he doesn’t think a state investigator will be called in to evaluate the incident further.

A student involved in the incident was seen talking with resident advisers and firefighters outside Muir Hall. The student declined to comment.

“I haven’t personally seen an incident like this in a dorm room where we’ve had an explosion of some type of battery-power anything,” Flatos said. “But we all hear stories about batteries that overheat and explode and this sounds like that’s what happened.”