Man accused of killing California police officer left behind cryptic suicide note: police

A man accused of gunning down a 22-year-old California police officer before turning the weapon on himself left behind a bizarre suicide note about "ultra sonic waves," according to authorities.

Police say Kevin Douglas Limbaugh, 48, attacked Davis Police Officer Natalie Corona as she was responding to the scene of a three-car accident off Interstate-80 outside of Sacramento on Thursday evening.

This 2018 booking photo released by the Yolo County Sheriff's Office shows Kevin Douglas Limbaugh. Limbaugh was convicted in a battery case and agreed in November to surrender a semiautomatic rifle. (Yolo County Sheriff's Office via AP)

Limbaugh was found dead inside of his nearby home hours after the attack from what police say was a self-inflicted gunshot wound. An open-faced letter was discovered on the suspect's bed, blaming his crime on what appeared to be a bizarre conspiracy theory about the police department.

"The Davis police department has been hitting me with ultra sonic waves meant to keep dogs from barking," the typed letter stated. "I notified the press, internal affairs, and even the FBI about it. I am highly sensitive to its affect [sic] 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."

The note was signed "Citizen Kevin Limbaugh."

Lt. Paul Doroshov of the Davis Police Department said that Limbaugh was not involved in the car accident and described the shooting as "an ambush," NBC News reports. According to eyewitnesses, the suspect approached the scene of the crash on a bicycle as those involved were exchanging information.

Davis Police Chief Darren Pytel said Limbaugh suddenly opened fire on Corona, shooting her multiple times before reloading his weapon and firing at random bystanders. No one else was injured in the attack.

Firefighters attempted to rescue Corona, who was rushed to UC Davis Medical Center where she later died from her injuries.

Limbaugh was arrested in September 2018 and charged with battery with serious bodily injury after he allegedly punched a co-worker in the face at Cache Creek Casino in Brooks, Calif., according to the Sacramento Bee.

The newspaper reports that the case was resolved as a misdemeanor conviction, which resulted in him surrendering an AR-15 rifle to police in November.

Davis officers mourned Corona following her death, describing the slain cop as a "rising star" within the department.

"Natalie was just full of life and full of energy and just an absolute pleasure to be around," said Chief Pytel. "She loved being around everybody in the department."

"I've heard her described by our officers tonight as our daughter, our friend, and just a sister that we all wanted," he added. "This is just an absolutely devastating loss to the police department."

Corona, who followed in the footsteps of her father to become an officer, graduated from the police academy in July and was sworn in as an officer just two weeks before her death.