1 dead, multiple injured after shooting inside Las Vegas Athletic Club: Police

"We no longer have a threat to the public," Undersheriff Andrew Walsh said.

One person is dead and several others are injured after gunfire erupted inside the Las Vegas Athletic Club on Friday afternoon, according to police.

The suspect walked into the gym with a rifle, looking for the victim. When the victim was found, the suspect shot and killed him, a law enforcement official briefed on the incident told ABC News.

Investigators are reviewing security footage and believe they have most of the incident on video.

The attack was not random and police do not believe the assailant intended to commit a mass casualty attack, according to the official.

"This afternoon, officers from the Las Vegas Metropolitan Police Department were dispatched to a call for service," Undersheriff Andrew Walsh said during a press conference. "The details of that call indicated that there was a person armed with a weapon and shooting inside of the Las Vegas Athletic Club."

Officers arrived on the scene and engaged with the suspect, leading to an officer-involved shooting where the suspect was shot and pronounced dead at the scene, according to police.

Authorities say there is no longer a threat to the public.

"There have been additional victims who are being treated for injuries that they received, we believe, at this time, at the hands of the suspect," Walsh added. "We do have one person deceased inside of the gym."

The identities of the victims and the suspect have not yet been released.

"What I ask you all to make sure you push out is that we no longer have a threat to the public," he said. "The situation is stable and now the investigation process will proceed."

This is a developing story. Please check back for updates.