Psychology junior Darren Hoffmann, who was in the class at the time, said he initially mistook the noise for a spilled water bottle.

"My initial reaction was that their water was spilling," Hoffmann said.

Hoffmann described the man as being in his mid-50s, wearing a hat, gray sweatpants and a green jacket. He said the man was sitting in the same row of computers as him.

After the teaching assistant noticed what was happening, she asked the man to leave the room. He then sat on a bench outside the classroom, Hoffmann said.

The teaching assistant contacted campus public safety, reported the incident to the building’s facilities manager and dismissed the class.

Hoffmann said he was shocked by the incident, and questioned how an unauthorized individual was able to enter an academic space unnoticed.

"I was sitting right next to him and had no idea what was happening until I saw it with my own eyes," Hoffmann said. "He could’ve had a weapon, and none of us would have known."

Hoffmann said he has heard of similar incidents on campus, including one in which a man refused to leave a recitation class last semester. He said the incident raised broader concerns about MSU’s policies on public access to academic buildings.

"After everything that’s happened on this campus, you’d think security would be a bigger priority," he said. "If this had happened in a bigger lecture hall, it would’ve been a much bigger deal."

Hoffmann said the man was still in the building as he exited and it is unclear whether the man was removed from campus.

MSU Department of Police and Public Safety spokesperson Nadia Vizueta said that in situations like this, students should call 911. If calling isn’t possible, texting 911 is also an option.

For suspicious activity that is not an emergency, students can call MSU DPPS at (517) 355-2221. In emergencies, 911 remains the recommended option, Vizueta said.