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Dennis Rader, the Wichita, Kansas, serial killer who dubbed himself BTK (for bind, torture, kill), really liked to write. In fact, it was his own notes and letters rife with misspellings and grammatical errors to the media and police that ultimately resulted in his capture. Now, 18 years after Rader was ordered to serve 10 consecutive life sentences for murdering 10 people from 1974 to 1991, investigators are finding potential clues to cold cases in the journals, notebooks, manuscripts and other documents seized after his arrest.

Some of those cold cases are now heating up: Authorities last week named Rader as the prime suspect in unsolved murders in Oklahoma and Missouri. As part of their investigation into the 1976 disappearance of 16-year-old cheerleader Cynthia Dawn Kinney in Pawhuska, Oklahoma, Osage County Sheriffs officials on Aug. 23 dug up the property where Raders family home once stood in Park City, Kansas.

Authorities said they found incriminating evidence, including possible restraints and a pantyhose ligature. Osage County Undersheriff Gary Upton told HuffPost there were also trophies which could lead to the identification of yet another victim.

My hope in the future is to perhaps at least reveal a picture of one of those sets of items, because it obviously belongs to a female victim, he said. And I think somebody seeing it would perhaps know who it belonged to.