ACTON (CBSLA) — A deadly shooting that killed one firefighter and left another one in critical condition could have been fueled by a workplace argument, sources at the Los Angeles County Sheriff’s Department said.

Authorities with the LA County Coroner’s Office identified the shooter Wednesday evening as 45-year-old Jonathan Patrick Tatone.

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The name of the victim has not been officially released. However, La Habra City Councilman Jose Medrano identified the deceased firefighter as Tory Carlon.

Preliminary interviews by deputies investigating the incident indicate that “There was an argument over workplace performance.”

Another source with the LASD said “It sounds like they didn’t like each other,” but didn’t elaborate further.

Authorities believe after the shooting, the suspect in Acton, set it on fire and took his own life.

Thursday, firefighters deterred people from bringing flowers to the fire station and instead encouraged people that would like to show support for the victim to donate to the Carlon family’s GoFundMe page. It can be found here.

“Going to fire station right now, we would heavily discourage that,” said  Jonathan Matheny of the LA Couty Fire Department. “It is a crime scene.”

According to authorities, the off-duty firefighter opened fire at about 10:50 a.m. Tuesday at L.A. Co. FD Station No. 81 in the 8700 block of Sierra Highway in Agua Dulce.

“Knowing that this could have happened to any of us, knowing that there is a mother or father, a husband or wife, children that are grieving beyond [what] words can even comprehend right now,” Jonathan Matheny, a spokesperson for the Los Angeles County Fire Department, said. “That’s hard to swallow.”

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The Los Angeles County Sheriff’s Department said the fire was reported at about 11:30 a.m. Tuesday, but since they did not immediately know what was inside, the bomb squad responded to the scene while ground crews and water-dropping aircraft worked for hours to put the blaze out.

“The suspect is saying he’s gonna shoot at anybody that approaches,” a dispatcher could be heard telling first responders.

Once investigators were able to get into the property, they found who they believed to be the shooting suspect dead in a pool from a self-inflicted gunshot wound.

“This is the most difficult day that I personally have ever experienced with the Los Angeles County Fire Department seeing our brothers and our sisters in harm’s way in this manner,” Matheny said.

The home, in the 2600 block of Bent Spur Drive in Acton, was designed by the late Bel Air architect Martin Gelber, according to online records, and was sold last July for $700,000.

“What is scary for me though is that if I would have gotten here earlier knowing he is an active shooter, I don’t know what would have happened,” said Black Webber, a neighbor.

At a vigil Tuesday night in Acton, a friend of the deceased firefighter described him as a loving father to three girls.

“When it comes to being a father, when it comes to being a fireman, when it comes to being a mentor, there was nobody that could parallel that, he taught me much about being a better father for my girls and being there,” he told the gathered crowd.

The slain firefighter was a 20-year veteran of the department.

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