One of three victims in a shooting on the campus of Old Dominion University in the US state of Virginia has died, the university's police said on Thursday.

At a news conference Thursday afternoon, Garrett Shelton, the university's chief of police, said that there was a third victim who went to the hospital independently, noting that the two surviving victims appear to be in stable condition.

Shelton added that authorities are "very early" in the investigation.

An earlier alert from the university said that two people were injured and the shooter was neutralized.

"Earlier today, an armed individual opened fire at Old Dominion University, leaving one person dead and two others wounded," FBI Director Kash Patel said on X.

"The shooter is now deceased thanks to a group of brave students who stepped in and subdued him -- actions that undoubtedly saved lives along with the quick response of law enforcement," he said.

Patel also noted that the FBI is now investigating the shooting as "an act of terrorism."

The university, founded in 1930, serves some 24,000 students, according to its website.

US Army Secretary Dan Driscoll posted on X that he was "deeply saddened" to hear about the shooting and the two Army personnel who were injured.

University President Brian Hemphill said in a statement to the school community that Old Dominion had "faced a tragedy" and thanked police and emergency responders for their swift intervention.

Virginia Governor Abigail Spanberger wrote on Facebook that she had spoken with university leadership and was mobilizing state support to assist with the situation.

(With input from agencies)