Davis, CA – The gunman who assassinated Davis Police Officer Natalie Corona as she was investigating a three-car pileup on Thursday night left a cryptic note in his residence before he fatally shot himself, police said.

The incident occurred at approximately 6:45 p.m., when 48-year-old Kevin Douglas Limbaugh rode up to the crash scene on a bicycle and opened fire on the 22-year-old officer, CNN reported.

“This clearly to us looks like an ambush,” Davis Police Chief Darren Pytel said, according to the Woodland Daily Democrat. “Based on how dark it was, we’re speculating that she never even saw him.”

Christian Pascual, who was driving one of the vehicles involved in the collision, said he got out of his vehicle after the wreck and was exchanging information with the drivers of the other two vehicles when Officer Corona arrived on the scene, The Modesto Bee reported.

“I gave her my license and she was just about to give it to me,” Pascual told the paper. “That’s when I heard the shots.”

The gunman was directly behind Pascual when he opened fire on Officer Corona, he said.

“The person was behind me and all of a sudden I heard gunshots,” Pascual said.

The shooter fired at the officer over his right shoulder, so close to his ear that Pascual had some hearing loss from the gunshot on Friday morning, according to The Modesto Bee.

He said he instinctively ducked when the gunfire began.

“I just knew that I had to get out of there once I saw the gun and what was happening,” he said. “I count myself pretty lucky that he didn’t think of me.”

“When I looked up and I saw the officer on the ground he was already walking due west toward C Street, like just shooting at what looked like random people to me,” Pascual explained.

Limbaugh reloaded his weapon and fired at other first-responders as they arrived at the scene, hitting one firefighter in the boot, KOVR reported.

His bullets also hit a passing bus and a woman’s backpack, according to the San Francisco Gate.

Officer Corona was transported to University of California – Davis Medical Center where she succumbed to her gunshot wounds.

At least one of the rounds hit her in the neck, Chief Pytel told the Woodland Daily Democrat.

Police soon tracked the suspect down using the contents of a backpack he had ditched at the scene of the ambush, CNN reported.

They cornered him at his residence in the 500-block of Fifth Street – approximately a block away from the murder scene, according to The Sacramento Bee.

Inside, Limbaugh chatted casually with his roommates and behaved as if nothing had happened, Chief Pytel told the Woodland Daily Democrat on Friday.

At one point, he wandered outside in a ballistic vest and watched as law enforcement officers converged on his home.

The second time he came out, he was armed, the San Francisco Gate reported.

“He shouted some stuff, went back in and came back out with a firearm, then went back inside, pushed a couch in front of the door and officers heard a gunshot,” the chief told the Woodland Daily Democrat.

Over the course of several hours, they attempted to coax Limbaugh into surrendering using a loudspeaker and floodlights, The Sacramento Bee reported.

They eventually deployed a robot into the home, and set off flash bang grenades.

“The shooter had been found, deceased, inside a home near 5th and E St in Davis with what appears to be a self-inflicted gunshot wound,” the Davis Police Department tweeted at 1:28 a.m. on Friday.

Inside his home, police found a short, typed letter that referenced his disdain for the Davis Police Department.

The letter was lying “open-face” on a bed, a Davis Police Department Lieutenant Paul Doroshov told KOVR.

“We can only speculate that it was there to be seen,” Lt. Doroshov added.

“The Davis police department has been hitting me with ultra sonic waves meant to keep dogs from barking,” the letter read. “I notified the press, internal affairs, and even the FBI about it. I am highly sensitive to its affect on my inner ear.”

“I did my best to appease them, but they have continued for years and I can’t live this way anymore,” Limbaugh wrote, before signing off as “Citizen Kevin Limbaugh.”

Lt. Doroshov said he is not a mental health specialist, and that he would let the letter “speak for itself.”

The lieutenant didn’t mention if the note may be a ruse to feign mental illness.

“People can read it and make the inferences that they want to make,” he added.

There is no record of Limbaugh having filed his complaints with the Davis Police Department, despite the claims he referenced in the letter, police said.

Investigators also do not believe Officer Corona had any prior contact with Limbaugh.

“He wasn’t on the radar as somebody who was continually calling in, expressing hate for us,” Lt. Doroshov said.

According to Yolo County court records, Limbaugh was arrested with battery causing serious injury after he allegedly assaulted his coworker at the Cache Creek Casino Resort in September of 2018, KOVR reported.

The charge was reduced to a misdemeanor as part of a plea agreement, and Limbaugh was sentenced to just eight days in jail and three years of probation.

As a condition of his sentence, Limbaugh was ordered to surrender his registered AR-15.

He used two semiautomatic pistols during the ambush on Thursday night – neither of which were registered to him, KOVR reported.

The 9mm and .45-caliber handguns were recovered from inside his home, and investigators are looking into their registered owner, according to The Sacramento Bee.

Probation officials said they witnessed no indications of mental health issues during their interactions with Limbaugh, and said he had no other criminal history prior to the battery offense.

His former roommate described Limbaugh as a “regular guy,” and said he “didn’t see this coming at all.”

Limbaugh lost his job at the casino after the assault, and had been unhappy at work long before that, the unnamed roommate told The Sacramento Bee.

“Kevin had a troubled life and felt trapped and had deep anger issues that he never let any of his friends see,” the roommate said.

“He was making great money but I could tell he absolutely hated his job at the time,” he added. “He might’ve felt like he just couldn’t get his life back together after losing his job at the casino.”

Limbaugh’s neighbors said they didn’t know him well, and that he generally kept to himself.

Three to five people usually lived in the home at any given time, they noted.

“It was like a hangout house,” one neighbor said. “There were always people coming and going.”

Prior to arriving in Davis, Limbaugh moved around the country, spending time in Florida, Michigan, and New Mexico, The Sacramento Bee reported.

He had a couple of traffic citations over the years, owes a $135 fine in Fort Myers, and never paid a $9,745 tax lien in New Mexico, according to the paper.

Officer Corona began serving the Davis Police Department as a community service officer in 2016, The Sacramento Bee reported.

When the agency ran out of money to fund her position at one point, she kept showing up to work anyway, and volunteered her time instead, Chief Pytel said.

“I haven’t seen anybody work harder in a part-time capacity and be more motivated to be a police officer than Natalie,” he explained. “She was just an absolute star in the department and someone that pretty much every department member looked to as a close friend, a sister.”

Officer Corona graduated from the Sacramento Police Department training academy in July of 2018, and wrapped up her field training just two weeks ago.

“We’re just absolutely devastated about the loss,” Chief Pytel said.

Officer Corona’s father, a 26-year veteran of the Colusa County Sheriff’s Office, pinned his daughter’s police badge onto her uniform during her swearing-in ceremony in August of 2018, the Pioneer Review reported.

“We are extremely proud of Natalie and all her accomplishments at such a young age,” retired Colusa County Deputy Jose Merced Corona said at the time, according to The Sacramento Bee. “She is very excited to be a police officer and is very dedicated to the profession of law enforcement.”

Deputy Corona said his daughter was determined to follow in his footsteps, KTXL reported.

“She would always call me ‘brother cop,’ and I would say, ‘you can’t call me brother cop because you’re not there yet. You don’t have a right to call me brother cop, you’re not there yet,” he told the news outlet.

“When she graduated from the academy, she says ‘OK, so now can I call you brother cop?’ And I said ‘yeah,’” Deputy Corona remembered fondly.

“She just enjoyed her job. She would come home, and she would be beaming,” he said.

Despite their loss, Deputy Corona said his family is focusing on remembering Officer Corona’s generosity and her dedication to her duty.

“We’re not angry,” he told KTXL. “You know we’re going to grieve, and the individual is not with us any longer, so we’re very faithful people.”

“I think she died doing what she loved to do. She knew that was a possibility, and I think she embraced that,” he said.