A total of three federal agents were involved in a deadly shooting at the Long Beach Federal building Thursday afternoon, investigators said during a news conference Thursday night.

After an apparent dispute, a homeland security investigations agent fired several rounds at a co-worker in their seventh-floor office space at 501 W. Ocean Blvd., said Steven Martinez, assistant director in charge of Los Angeles FBI.

The victim sustained multiple gunshot wounds before another agent working nearby intervened and fired his weapon, killing the shooter, Martinez said.

The victim, repeatedly referred to as a man, was listed in stable condition Thursday night at a local hospital, officials said.

Authorities characterized the deadly shooting as workplace violence, and said they believed the shooter acted alone.

Neither victims were identified pending families’ notification, said Claude Arnold, special agent in charge of U.S. Immigration and Customs Enforcement (ICE) homeland security investigations in Los Angeles

“We are like a family in this agency of law enforcement,” Arnold said. “When something like this happens, it affects us all.”

The FBI will lead the investigation into the incident, and Long Beach Police will assist, said Robert Luna, Long Beach police deputy chief.

Officials did not take questions during Thursday night’s news conference, claiming they were in the preliminary stages of the investigation.

The conference was introduced as an opportunity to “correct misinformation reported” throughout the day.

A flurry of information, at times conflicting, came through police, fire and news media outlets.

Aerial communications from Long Beach Police described three agents involved in the shooting, and reported that two of them were pronounced dead at the scene.

"The initial reports were false. Two agents shot...one killed...the other wounded," ICE spokeswoman Virginia Kice wrote in an email.

Kice’s agency released a statement late Thursday claiming two of their agents were involved in the shooting, which took place shortly before 6 p.m.

The statement described two officers involved. One was pronounced dead at the scene and a second was sent to a nearby hospital, according to the statement.

Preliminary reports described a shootout involving two people, including a possible ICE officer officer.

More than a dozen police vehicles and at least two fire trucks lined the sidewalks surrounding the heavily-secured building shortly after the incident.

The shooting is being investigated by ICE's Office of Professional Responsibility, the Long Beach Police Department and the FBI, according to ICE's statement.

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