Emergency crews responded to the University of Missouri for a hazardous materials call.
According to law enforcement, a call came in around 4:50 p.m. Wednesday for a report of an "unknown substance" coming from underneath a door in Middlebush Hall.
A sign on the door stated to call 911 in case of an emergency. Another sign said there were hazardous materials within the room.
The building was evacuated and there are no injuries.
Officials said they determined it was a hydraulic issue with an elevator and that the area is safe.