Bombshell breakthrough in decades old cold case murder of California teen as cops finally find her killer through DNA

A bombshell breakthrough has been made in a decades-old California cold case murder as the killer has been identified through DNA.

The horrific murder took place in 1986, when the body of 19-year-old Cathy Small was found in the middle of a leafy street in South Pasadena. The teen had been stabbed and strangled - but her killer was never found, until now.

Police revealed that Small's murderer is notorious serial killer William Lester Suff, 73, also known as the Riverside Prostitute Killer and the Lake Elsinore killer. 

Suff is already on death row for the murders of 12 other women, whom he killed between the 1980s and early 1990s. 

During a news conference on Tuesday morning, Los Angeles County Sheriff Robert Luna confirmed the identity of the killer.

In 1986, 19-year-old Cathy Small's (pictured) body was found in the middle of the 800 block of Bank Street in South Pasadena

Suff confessed to Small's killing after being confronted with DNA evidence, according to officials. 

'It is horrifying that her life was taken away so violently and in such a tragic way,' L.A. County Supervisor Kathryn Barger said.

The Sherriff's Department said the case has 'haunted the community' for decades.

'Today we stand before you to announce that justice will be served for Cathy and her family. Although almost four decades have passed, law enforcement never gave up on this case,' Barger said. 

Suff's other confirmed victims include: Rhonda Jetmore, Kimberly Lyttle, Christina Leal, Darla Jane Ferguson, Carol Lynn Miller, Cheryl Coker, Susan Melissa Sternfeld, Kathleen Leslie Milne, Sherry Ann Latham, Kelly Marie Hammond, Catherine McDonald, Delliah Zamora and Eleanor Casares. 

There are several other murders that were attributed to Suff - though he was never charged.  

The killer, Suff (pictured), is already on death row for the murders of 12 other women, whom he killed between the 1980s and early 1990s

Suff was finally arrested in 1992 after a routine traffic stop after a police officer found a bloody knife and objects believed to be related to the killings. 

A Riverside County jury found Suff guilty of killing 12 women - and attempting to kill  another. 

This cold case is just the latest of many to be cracked using DNA technology. Similar testing has been used to capture monsters such as the Golden State Killer and the Grim Sleeper. 

DNA was first used to help investigate a criminal case in 1986 and since then, hundreds of cases have been solved thanks to genealogy research advances.

Genetic genealogy, which is the practice of entering a DNA profile into a public database to find relatives, has emerged as a powerful tool for identifying suspects who leave DNA behind at a crime scene.