Police continue their search for Travis Decker, a Washington state man wanted in connection with the murders of his three daughters.

The Okanogan County Sheriff’s Office announced Thursday that investigators believe Decker may be traveling on or near the Pacific Crest Trail in Okanogan County.

As CrimeOnline previously reported, the Wenatchee Police Department said officers discovered 9-year-old Paityn Decker, 8-year-old Evelyn Decker, and 5-year-old Olivia Decker dead near the Rock Island Campground Monday.

Police suspect that, Decker, 32, killed them during a planned visitation and then fled the area.

Investigators found the girls roughly 75 to 100 yards down an embankment, with zip ties and plastic bags scattered nearby. Court documents stated that the girls’ wrists were or appeared to be zip-tied, and each had a bag over her head, indicating they had been suffocated.

“He was an engaged father. He did have some limitations on his parenting time due to his mental illness,” Arianna Cozart, a lawyer for the girls’ mother, Whitney Decker, said, according to KFYR-TV.

Authorities said that Decker served in the military and “may pose a significant risk, if approached.”

Decker’s skills as an outdoorsman, along with his training from mountain survival school and service in the U.S. Army, are likely to complicate the search efforts, law enforcement said.

“It sounds like at times he would go out and would be (living) off grid for sometimes up to two and a half months,” Chelan County Sheriff Mike Morrison said.

“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.”

The Okanogan County Sheriff’s Office said Decker could be anywhere in the vicinity of the Pacific Crest Trial and urge residents to “remain vigilant” by locking their doors, keeping blinds and curtains open, and leaving exterior lights on at night.

The U.S. Marshals Service announced a reward of up to $20,000 for information that leads to Decker’s arrest.

Anyone with information on his whereabouts is urged to contact the CCSO tip line at 509-667-6845 or submit information online at https://www.co.chelan.wa.us/sheriff/forms/submit-a-tip.

Check back for updates.

[Feature Photo via Whitney Decker/Facebook]