Colorado Springs, CO – Pikes Peak Christian School was closed Thursday due to a carbon monoxide leak coming from a dysfunctional furnace, the school’s director said Thursday.

Carbon monoxide started leaking from the furnace through vents in the building and was first recognized at 7:45 a.m., said Matt Johns, the school director.

Students were moved out of areas where the gas was suspected, Johns said, before then being moved outside. The fire department and an ambulance responded, he said, and no injuries were reported.

Johns said school was canceled Thursday as it will “take a while to clear the whole building.”