Palmer High School in downtown Colorado Springs was evacuated Wednesday when a fire extinguisher was set off, prompting a false smoke alarm, School District 11 officials said.

The students will be dismissed from Erps Gym, on the corner of Wahsatch and Platte avenues, said school district 11 spokeswoman Devra Ashby.

Fire trucks surrounded the school at 301 N. Nevada Ave. about 1:30 p.m. amidst reports of smoke in the building’s basement, Ashby said.

According to a tweet from the fire department, the haze left behind by the fire extinguisher was mistaken for smoke.

Palmer High School officials did not know how the extinguisher was set off or whether any students were responsible, Ashby said.

Palmer high school students stand outside after a fire alarm was falsely activated at the school. Nevada Avenue was closed for a time as crews responded. Photo by Michael Ciaglo