Dennis Lynn Rader is an American serial killer known as BTK, the BTK Strangler or the BTK Killer. Between 1974 and 1991, BTK killed ten people in Wichita and Park City, Kansas. Rader pleaded guilty and was sentenced to 10 consecutive life sentences.
 
Parade January 2016 from BTK's newspaper with his handwriting at the top of the front and again Rader has written the same three letters along the top of pages 9 pages including the front cover which includes another word or abbreviation.