Police declined to publicly identify the assailant, going so far as to avoid any mention of the suspect's gender, nor did they give any information about the four victims struck by gunfire - three fatally - or their connection to the university.
The surviving gunshot victim was listed in stable condition, according to Sheriff Kevin McMahill of the Las Vegas Metropolitan Police Department.
He said several other people suffered panic attacks during the pandemonium, and a number of officers were treated for minor injuries sustained during a search of the sprawling campus for any additional victims or suspects. None were found.
No mention was made of a possible motive for the violence, and police did not disclose the type of firearm used.
Vincent Perez, a professor at the school, known by its initials UNLV, told MSNBC by phone that he had heard a lot of gunfire before taking cover on campus.
"I would say just seven, eight shots, one after another, loud and very loud," he said. "As soon as we heard that, we ran back inside and we realized this is a real shooting, and there's an active shooter on campus."
MNA/PR