The University of Nevada, Las Vegas campus turned to chaos Wednesday when a gunman opened fire as he roamed the halls, killing three people and critically wounding a fourth.  

The gunman, who died in a shootout with police, was a 67-year-old career college professor who had recently unsuccessfully sought a job with UNLV, a law enforcement official told The Associated Press anonymously.

The shooter had connections to schools in other states, having previously worked for schools in Georgia and North Carolina, including East Carolina University, sources told CNN. 

Police have the gunman’s phone and are examining it for a possible motive, according to Scripps News Las Vegas. Since the victims were not students, there may be reason for police to believe the attack was targeted.

The shooting happened around noon on Wednesday, when the shooter opened fire on the fourth floor of the campus’ Beam Hall before moving to several other floors. Police engaged the gunman outside the building.

“If it hadn’t been for the heroic actions of one of those police officers who responded, it could’ve been countless additional lives taken,” said Sheriff Kevin McMahill of the Las Vegas Metropolitan Police Department.

The surviving victim who was shot is hospitalized in stable condition, according to police.

This marked the deadliest shooting in the city since October 2017, when 59 people were killed after a shooter opened fire on a music festival from the Mandalay Bay hotel overlooking the Vegas strip. That was the deadliest mass shooting in modern American history.

“I’m trying to keep myself calm. This is my second shooting,” said a woman on campus at the time. “This is just more stuff in therapy to talk through.”

An investigation remains ongoing. 

SEE MORE: 3 dead and 1 injured after shooting at UNLV in Las Vegas

3 dead and 1 injured after shooting at UNLV in Las Vegas

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