UPDATED 3:30 p.m. Monday, April 15: Suspect in Cowlitz deputy’s slaying is half-brother of Rainier police chief’s killer

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Two police officers fatally shot the suspect in the killing of a southwest Washington sheriff’s deputy after the suspect was seen running out of the woods with a firearm, ending a lengthy manhunt, authorities said.

The suspect killed Sunday night has not been identified. The investigation into the killing continued Monday and Cowlitz County Sheriff Brad Thurman said he could not provide details about a motive.

Kelso Police Chief Andrew Hamilton on Monday described the slain suspect as "an armed combatant” but didn’t specify whether he fired at officers. The man is suspected to have shot Cowlitz County Deputy Justin DeRosier on Saturday.

Two other men — brothers Matthew and Michael Veatch — were arrested. Matthew Veatch was jailed on suspicion of first-degree rendering criminal assistance. Michael Veatch was taken into custody on an unrelated warrant but was being questioned in the deputy killing, an official said.

Sgt. Rich Fletcher and Detective Tim Gower of the Kelso Police Department have been identified as the officers involved in the Sunday evening shooting, which happened in the area of Spencer Creek Road in Kalama. Both have been placed on paid administrative leave, as is standard protocol after police shootings.

No officers were hurt in the encounter, according to the Cowlitz County Sheriff’s Office, and there’s no danger to the public.

The shooting came amid a manhunt for the suspect or suspects responsible for the death of DeRosier, who was shot after being sent to check on a disabled vehicle that was blocking a road about three miles east of Interstate 5 late Saturday, authorities said.

DeRosier, a 29-year-old father and husband, died during surgery at PeaceHealth Southwest Medical Center in Vancouver.

He graduated from Kelso High School and Washington State University and signed on with the Cowlitz County Sheriff’s Office in 2016.

Darren Ullmann, Cowlitz County undersheriff, said few law enforcement officers want to serve more than DeRosier did. The deputy loved his job, Ullmann said, and “was incredibly good at it.”

“He will be with us forever, and he’ll be truly missed,” Ullmann said.

-- Jim Ryan; jryan@oregonian.com; 503-221-8005; @Jimryan015

The Associated Press contributed to this report

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