"I want to be clear that it's not a fire," Olsen said. "There is a yellowish-orange light bulb, and my working assumption is that it’s for safety purposes and for workers who are working in dark conditions. An optical illusion made it seem as if flames were coming when the steam combined with that light."

Olsen said the issue has been resolved and the Union reopened.

Student Life and Engagement, or SLE, Communications Director Kat Cooper said the cause of the steam release is still unknown.

"The firefighters on campus are still investigating the incident as we speak, but they have deemed it same for the students to return to the building," Cooper said. "Currently, the investigators are still working to eliminate any risks. We want to make sure this doesn't happen again."

Michigan State University Police Department Sergeant Steven Beard said that although there wasn't a fire, someone called 911 to report one.

"The fire department checked the building, and it was clear," Beard said.

Cooper said responders got to the Union on time, students were evacuated in an orderly fashion and panic was resolved.

Strange matter employees Lee Cushard and Henry Pointon were working at the union when they were suddenly rushed out by police without explanation. Both Cushard and Pointon said they did not smell a fire, believing that to only be a rumor.

Construction management junior Blake Brykalski said he was attending a career fair when he first saw fireman flooding into the building.

"It seemed like they were in a little bit of a hurry, but I didn’t see any kind of fire on our side because we were so close to Campbell Hall," Brykalski said.

Construction management freshman Jace London said they were on the third floor of the building for a club presentation night when the fire alarm was pulled and they were told to evacuate.

“I’ve been sitting by the entrance where the police officers were, and I heard over the radio that there was definitely smoke on the fifth floor on the roof on the northside of the building,” London said. “They’re not letting anybody back in, so if you left your stuff in there you have to wait until after it’s over, and they want everybody away from the building so they made us go across the street.”

Arts and humanities freshman Josephine Vanderhyde said she walked fifteen minutes to the Union to find out what was happening.

“I was like, ‘I thought there was a fire at Wilson earlier, but I didn’t see anything about the Union,'” Vanderhyde said. “So (I) decided to come down to investigate because we weren’t sure what was going on.”