Three girls believed to have been killed by their father were found zip-tied and with plastic bags over their heads in a remote part of Washington state, according to court documents obtained Wednesday.
A preliminary examination concluded that the girls, ages 5, 8 and 9, likely died by asphyxiation, according to an affidavit in support of an arrest warrant for their father, Travis Decker.
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WATCH HEREA full autopsy is expected to be released Thursday, Chelan County Sheriff Mike Morrison said at a Wednesday evening news conference, noting that the girls are a "motivating force for us" in the search for Decker.
Decker, 32, is wanted on charges of first-degree murder and kidnapping. The U.S. Marshals Service on Wednesday announced a $20,000 reward for information leading to his capture.
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SIGN UP The military veteran is not known to be armed but should be considered dangerous, officials said.
Morrison said detectives learned from speaking to Decker's family that he is well-versed in outdoor survival and would sometimes go "off-grid" for months without returning. Decker “was an outdoorsman since he was a kid,” Morrison said, adding that outdoor survival is something he does recreationally.
The sheriff also noted that Decker may have retained survival training from his time in the military.
Morrison said it's possible Decker could have prepared in advance, scoping out the area and leaving supplies around to allow him to survive in the wild for a long period of time. Outdoor survival experts are assisting in the search for Decker as well, Morrison said.
Investigators are going through electronics found at the scene, including a cellphone. "We are optimistic we will find him shortly," Morrison said.
According to the affidavit, Decker’s ex-wife initially reached out to authorities last week when he failed to return the girls after a visit and would not take her phone calls.
The former couple was married for seven years but divorced in a process Decker’s ex-wife described as civil, the affidavit states.
She told a detective in Wenatchee, roughly 150 miles east of Seattle, that there had been no issues with recent visitations and described her ex-husband as communicative about their daughters, according to the affidavit.
“She reiterated that Decker has never failed to return the kids,” the affidavit states.
Decker’s ex-wife said they agreed to a parenting plan last September, but the detective noted that Decker refused to sign the document after he became homeless, according to the affidavit.
As part of the plan, Decker was supposed to seek mental health treatment and domestic violence anger-management counseling but had not done so, according to the affidavit.
A National Guard spokesperson said Decker became an active-duty service member in 2012 and was transferred to the National Guard in 2021. He is still in active duty but has been absent from monthly drills for roughly one year, the spokesperson said.
A weekend-long countywide search for the girls led authorities to obtain an arrest warrant for Decker on charges of custodial interference. Just before 4 p.m. Monday, his pickup was found unoccupied near a campground west of Wenatchee, according to the affidavit.
Along with car seats, blankets and food, Decker's wallet was inside the vehicle, the detective wrote. Two bloody handprints were spotted on the tailgate and zip ties, and plastic bags were scattered around the truck and along the path to the girls' bodies, according to the affidavit.
The girls were found down an embankment, roughly the length of a football field away from Decker's truck, the detective wrote. In addition to the bags over their heads, the girls had zip ties around their wrists or showed signs of having been zip-tied, according to the affidavit.
The Chelan County Coroner positively identified the children as the missing girls, according to the affidavit. Reached by phone Wednesday, Chelan County Coroner Wayne Harris declined to provide details about their deaths because an autopsy has not been completed, he said.
In an online fundraiser, a music teacher who previously taught the girls described them as "a true light in this world."
"It is a darker place without them," she said.
NBC News' Lindsay Good, Andrew Blankstein and Rebecca Cohen contributed.
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