On Sunday, the FBI revealed it is looking into a possible link between the Santa Cruz County killing and the death of an officer outside the federal building in Oakland last month.
RELATED: FBI seeking help identifying suspect's van in Oakland Federal Building shooting
Around 1:30 p.m. Saturday, the sheriff's office received a report of a suspicious van on a turnout at Jamison Creek Road near Ben Lomond. The caller said they saw guns and bomb-making devices inside the vehicle.
When deputies arrived at the scene they saw the van leave and followed the vehicle. As the van pulled into a driveway on Waldeberg Drive, the officers were ambushed with gunfire and many improvised explosives, Hart said.
Sergeant Damon Gutzwiller, 38, was shot and taken to the hospital where he was pronounced dead.
"In my 32-year career, this is the worst day I've ever experienced," Sheriff Jim Hart said as he began the news conference.
Gutzwiller worked for the sheriff's office since 2006 and is survived by his wife, young child and another on the way. Hart described him as a courageous, intelligent, sensitive and caring man.
"Words cannot express the pain we feel for Damon and his family," Sheriff Jim Hart said, "He was the kind of person we all hope to be. Today, we lost a hero. We are grateful to have known him and we mourn with his family."
WATCH: Vigil held for Sergeant Gutzwiller
During the ambush, another officer was struck by either gunshot or shrapnel from the explosives, then struck by a getaway vehicle, Hart said. The officer was taken to the hospital and officials say they are in stable condition and expected to recover.
Calls of carjacking soon followed as officers from other departments arrived to the scene.
The FBI confirmed to ABC7 that the agency is looking into a possible connection between the Santa Cruz County shooting and the shooting death of Officer Pat Underwood in Oakland last month.
Security officer Underwood was shot and killed near George Floyd protests in Oakland on the night of May 29.
The FBI is now looking for a white van in connection to that shooting.
In a statement on Sunday, the FBI said, "We are actively working with the Santa Cruz Co Sherriff's Department to see if there are any connections to the shooting at the Oakland federal building. At this time, we have no new information to release."
WATCH: Santa Cruz Co. Sheriff Jim Hart's full news conference on Ben Lomond incident
The suspect, Steven Carrillo of Ben Lomond, was shot during his arrest and transported to the hospital. Hart said Carrillo is expected to survive and will be arrested for the murder of Sergeant Gutzwiller and other felonies.
The ABC7 I-Team has new information on Carrillo since officials identified him. The I-Team has learned he is 32 years-old and an active duty US Air Force sergeant based out of Travis Air Force Base in Fairfield.
His former colleagues are baffled that, in effect, a cop would target cops. His friend, Justin Ehrhardt, is a retired Air Force military police officer.
"It just breaks my heart, the officers who were impacted and their families, we're supposed to be on the same side."
Ehrhardt told ABC7 News' Dan Noyes that he spoke with Carrillo just a month ago, about his plans to retire from the service.
(Carrillo) "Was looking forward to getting out of California, but there was nothing even brought up in a negative light bbout anything with police at all.," Ehrhardt said.
Carrillo's Facebook page has been taken down, but Noyes captured his profile picture that lists him as a Libertarian and his friends have been sending screenshots from the past month. It's clear Carrillo was growing increasingly upset about police excessive force. On June 5 he wrote, "Who need antifa to start riots when you have the police to do it for you..."
Just minutes before Saturday's killing, he posted this from the Holocaust Museum - "the early warning signs of Fascism".
Justin Ehrhardt tells Dan Noyes that Carrillo was also having a hard time with his wife's suicide in 2018. She was an Air Force Airman 1st Class, found dead in an off-base hotel in South Carolina.
"A lot of regret, I think was there and it was just challenging for him. But even with all that none of us the people I talked to who were stationed with him even once thought this would happen at all," Ehrhardt said.
Sources tell ABC7 News' Dan Noyes that the ATF has taken a shell casing from the shooting in Ben Lomond to the lab in Washington, DC to be compared to the shooting at the Federal Building in Oakland. This is a very active investigation.
Stay with ABC7 News for updates on this developing story.