Serial Killer Communicating from Library?

The downtown Wichita (KS) public library was closed down for a brief time while police investigated a suspicious package that related to the serial killer BTK. “In October 1974, several months after four members of the Otero family were killed, BTK contacted The Wichita Eagle to say he had placed a letter in a mechanical engineering textbook at the library.” Police found the letter which said that “three suspects in police custody for the Otero killings were merely seeking attention.” More here from the Wichita Eagle.