DAVIS, Calif. -- A man who shot and killed a rookie police officer in Northern California before taking his own life during a standoff with police was a 48-year-old convict who had been ordered to surrender a semi-automatic rifle.
Kevin Douglas Limbaugh's name was released Saturday as investigators continued to investigate his motive for the attack.
Police now say Limbaugh left behind a letter claiming that the Davis department was attacking him with ultrasonic waves and that he could not live that way anymore.
The Sacramento Bee reports that court documents show Limbaugh was charged and convicted in a battery case last fall, and he agreed in November to surrender the weapon.
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The case stemmed from Limbaugh getting arrested in September for assaulting someone at Cache Creek Casino, Yolo County Sheriff's Sgt. Matthew Davis said.
Authorities have not determined where Limbaugh obtained the two semi-automatic weapons he was believed to have used in the Thursday night attack that killed 22-year-old Officer Natalie Corona in the college town of Davis.
Police said a gunman on a bicycle ambushed the officer, shooting her from the shadows as she investigated a car accident, then reloaded and narrowly avoided wounding others before walking home.
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At his house a few blocks away, he casually chatted with his roommate as if nothing happened and even went outside to watch as police from around the region began rushing to the shooting scene, Davis Police Chief Darren Pytel said Friday.
The gunman left behind a backpack that helped police track him to the house. The chief said as police began to surround it, he stepped outside wearing a bulletproof vest.
"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," Pytel said.
Police eventually sent a robotic camera in and found the shooter had shot himself in the head.
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Police found two semi-automatic handguns in the home.
The shooting devastated the Davis Police Department, which has about 60 sworn officers and about 30 other employees. Corona was the first officer in the department to die in the line of duty since 1959. She had only been patrolling solo for about two weeks, the chief said.
A candlelight vigil for the slain officer was scheduled Saturday night.
Suspect in death of Davis Police Officer Natalie Corona identified
OFFICER NATALIE CORONA
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