10 Serial Killer Crimes That Took Years To Solve

This killer is better known by his alias BTK, which stands for 'bind, torture, kill', a name he creepily bestowed upon himself.

His first known crime is the murders of a family of 4 in Wichita in 1974. The bodies were discovered by their son as he came home from school, Rader later left a note in a library book detailing the exact method of the murders. He continued to send out letters including one to a television station that listed possible names from himself including the one that would eventually stick; BTK. Over the next 17 years he would attack many people, some of whom escaped but others were not so lucky.

The case went cold until 2004 when Rader began communicating with the police again. In these letters he confirmed that he murdered another woman which led to the reopening of the investigation and the use of modern DNA techniques to track him down. In another letter he asked if he would be safe to send things via a floppy disk, the police said it would. They used the metadata on this disk to find clues as to his identity, such as the last user to edit the document being named 'Dennis'.

Using this new information the police put a warrant out for Rader and arrested him in 2005. He was tried and found guilty on 10 counts of murder, although he is believed to have stalked many more potential victims.