Law enforcement has tracked someone they believe to be Travis Decker - accused of killing his own children - in the Blewett Pass area of Washington state Tuesday evening, the Chelan County Sheriff’s Office said in a news release.

Authorities say they believe they spotted Travis Decker, an ex-soldier wanted in the deaths of his three daughters, in the remote backcountry of Washington state, after receiving a tip from hikers who said they saw a lone person who appeared to be

The investigation has "evolved and matured," and as a result, their approach to the investigation will also require a "change in tactics."