(CNN) —  

Last week, firefighters in southern California raced to save the lives of victims of a mass shooting. Just hours later, they sped off to battle two wildfires, several miles apart.

They’re still on duty four days later, fighting the Woolsey fire in Ventura and Los Angeles counties, and the Hill fire in Ventura County, said Los Angeles Fire Department Capt. Frank Lima, a union leader.

“Those are two national news stories just on their own, let alone back to back right in the same footprint of … 20 miles,” Lima, a vice-president of the International Association of Fire Fighters, said in an interview on Monday. “That’s tough, it takes a big emotional toll on you.”

“And as we’re processing it and we haven’t come down, then you throw another brick on there. … It gets a little bit heavier.”

About 20 firefighters from two Ventura County fire stations spent hours triaging victims of the shooting at the Borderline Bar & Grill in Thousand Oaks late Wednesday.

Ian David Long, a US Marine veteran, opened fire there and killed 12 people, including Ventura County Sheriff Sgt. Ron Helus, before taking his own life.

 Ventura County Sheriff Sgt. Ron Helus.
PHOTO: Ron Helus/Facebook
Ventura County Sheriff Sgt. Ron Helus.

Helus had been near the bar when the call came in, authorities said. He had been talking to his wife on the phone.

“Our members worked tirelessly on him to do everything they could to make sure he survived,” Lima said.

By 6 a.m. Thursday, the Ventura County firefighters, who were among a battalion of firefighters who responded to the shooting, returned to their fire stations.

Hours later, Lima said he looked up from the parking lot of the Borderline bar and saw “the whole sky was loaded with smoke.”

“And everybody just went,” he said of the Ventura fire fighters.

The Woosley fire doubled in size in a 90-minute period Friday morning to 8,000 acres. By Monday, it was up to more than 91,500 acres, and was about 20% contained.

The Hill fire in Ventura County had torched about 4,531 acres, and was 75% contained Monday.

The Ventura firefighters haven’t yet been able to turn their attention to their own homes, Lima said.

Lima, who has responded major national disasters such as September 11 and Hurricane Katrina in Louisiana, said the union offers offers counseling for the firefighters. Everyone process the stress of a crisis in different ways, he said.

“It’s like grieving. Everybody has family members, and some are quiet and some cry. Some don’t cry. Some want to be by themselves,” Lima said.

A third fire in Northern California also continues to burn. At its fastest, the Camp Creek fire, which started early Thursday, spread at more than a football field per second, or 80 football fields per minute. By Monday, it had torched more than 113,000 acres, killed 29 people and virtually destroyed the town of Paradise. It was about 25% contained by Monday morning, according to the state firefighting agency Cal Fire.

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Lima said he has talked to the firefighters who responded the shooting and the wildfires. They’re tired, he said, but running on adrenalin.

“They’ve got a fire raging down their back,” he said.

CNN’ Holly Yan and Susannah Cullinane contributed to this report.