(L) Evelyn Decker, 8; (M) Olivia Decker, 5; and (R) Paityn Decker, 9. The three sisters were found dead near Rock Island Campground in Washington state on Monday, June 2.
Pictured is 32-year-old Travis Decker.

Authorities in Washington have intensified the search for Travis Decker, who is wanted in the killing of his three young daughters.

The state's governor on June 6 said he would tap into emergency funds and Washington National Guard resources to aid in the search.

The bodies of Paityn Decker, 9; Evelyn Decker, 8; and Olivia Decker, 5, were found on June 2 at a remote campground. The girls' mother, Whitney Decker, reported to police that her ex-husband failed to return them after a scheduled custody visit on May 30, police said. The girls were found near Travis Decker's white truck having been suffocated, with Decker nowhere in sight, court records say.

Decker is wanted on charges of murder, kidnapping and custodial interference.

Gov. Bob Ferguson said on June 6 he was "tapping emergency funds and ordering Washington National Guard resources" to help in the search for Decker. Ferguson said he would also provide helicopters to law enforcement combing through remote areas of the state.

"As a parent, my heart goes out to Paityn, Evelyn and Olivia’s mom, Whitney, and all those who love them. The brutal murder of these young children has shocked our state. I’m committed to supporting law enforcement as they seek justice for Paityn, Evelyn and Olivia," Ferguson said.

He reiterated a warning from local authorities to keep windows and doors locked. Chelan County Undersheriff Dan Ozment previously told residents in remote areas of Chelan, Kittitas King, Snohomish, and Okanagan counties to remain on alert.

What happened to the 3 sisters?

The Decker sisters went with their father for a regularly scheduled custody visit on May 30 in central Washington but never returned. The parents were divorced, and Travis Decker was homeless and staying primarily in his truck. Whitney Decker reported them missing that day.

Washington State Patrol issued an Endangered Missing Person Alert (EMPA) alert for the girls on May 31 after authorities found criteria wasn't met for an Amber Alert.

Wenatchee police tracked Travis Decker's truck, a white 2017 GMC Sierra, and found it June 2 near Rock Island Campground, about 40 miles northwest of Wenatchee. Travis Decker was not there, but the bodies of Paityn, Evelyn and Olivia were about 75 to 100 yards away from the truck.

The girls likely died of asphyxiation, according to a probable cause affidavit. Each girl was found with a plastic bag over her head, and also showed signs of being zip-tied.

Decker could be hiding in wilderness, authorities say

Authorities said Travis Decker could be using his outdoor survival skills to be staying off law enforcement's radar. Decker went to mountain survival school and served in the U.S. Army, Chelan County Sheriff Mike Morrison said on June 4.

"It sounds like at times he would go out and would be (living) off grid for sometimes up to two and a half months," Morrison told reporters. "He could have scoped out this area before (he) put supplies out there and has the ability and the knowledge to survive for a long period of time."

Police have said he is a former military member with extensive training who "may pose a significant risk, if approached."

Chelan County Sheriff's Office said on June 5 it was narrowing its search for Decker after gathering "new information" in the case.

"Our teams have written and executed several search warrants around the area and on electronic devices that belonged to Travis Decker," Ozment said, adding that officials had "gathered new information which in turn has given us more leads to follow up on."

Contributing: Natalie Neysa Alund and Anthony Robledo, USA TODAY

This article originally appeared on USA TODAY: Search intensifies for Travis Decker, accused in slaying of 3 daughters

Reporting by Jeanine Santucci, USA TODAY / USA TODAY

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