SALT LAKE CITY, Utah (CNN) -- Minutes before Officer Thomas Cottrell was killed, police received an ominous call.
A woman in Danville, Ohio, said her ex-boyfriend took off with his weapons Sunday night and was looking to kill an officer, the Knox County Sheriff's Office said.
Authorities scrambled to warn Cottrell, who was a sixth of Danville's police department.
But less than 30 minutes later, Cottrell's body was found behind the Danville Municipal Building, the Sheriff's Office said. His weapon had been stolen, and his police car was missing.
Authorities identified the suspect as Herschel Jones III. After a brief foot chase, police arrested him.
It was not immediately clear whether Cottrell was targeted specifically, or if the assailant was trying to kill any police officer.
The Sheriff's Office is investigating the case.
Between January and November 2015, at least 30 U.S. law enforcement officers were shot to death, the National Law Enforcement Officers Memorial Fund reported.
According to preliminary data the fund compiled, 124 law enforcement officers died in the line of duty in 2015, a 4% increase from 2014, when 119 officers were killed. The leading cause of the 2015 deaths were traffic incidents, which killed 52 law enforcement officers: Thirty-five officers died in automobile crashes, 11 were struck and killed outside their vehicle, and six were killed in motorcycle crashes.
Also last year, 42 officers were killed by firearms, which was a decline from 2014, when 49 officers were shot and killed, the fund reported.
Utah officer slaying
One of the more recent slayings of an officer on duty happened in the Salt Lake City area Sunday.
Douglas Barney and another officer responded to a traffic accident and searched for two people who had fled, authorities said. Barney, 44, encountered a man who shot him, police said. The other officer was injured.
The alleged shooter, Cory Henderson, was also killed in the shootout. He had faced multiple state and federal charges going back more than 10 years, according CNN affiliate KUTV.
Henderson pleaded guilty to possessing an unregistered sawed-off rifle in 2005, and in 2010 pleaded guilty to felony possession of a firearm, KUTV reported. Both were federal charges.
Henderson also pleaded not guilty to federal drug and gun charges just last month, KUTV said.
At that time, a federal magistrate judge sent Henderson to a treatment center run by the Utah Department of Corrections. A representative told KUTV that Henderson walked away from the center on December 18.
Law enforcement agents were notified, and a fugitive warrant was issued.
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