Police have released a sketch of a suspect in the Halloween murder of 18-year-old Taylor Van Diest, and say DNA evidence has linked him to a sex assault six years ago.

The sketch shows a white man with a darker skin tone, between 25 and 26 years old. Police say the suspect has brown eyes, short dark hair, and is between 5-8 and 5-10 tall with a stocky build. He also has large, distinct sideburns and thick eyebrows.

The composite drawing was made from descriptions gathered after a sex assault on an employee at the Garden of Eden escort agency in Kelowna, B.C. on April 12, 2005.

RCMP Cpl. Dan Moskaluk told reporters Wednesday that DNA taken from the scene of Van Diest's murder in Armstrong matches samples gathered at the escort agency after the assault.

"Investigators can confirm the match; however, they do not have the outright identity of this person at this time," Moskaluk said, adding that the man is believed to be a resident of the Okanagan Valley.

Police are pleading with anyone who might have information about the suspect to come forward -- particularly family and friends who might have noticed warning signs before and after the killing.

Moskaluk notes that the man responsible for killing Van Diest might have come home after Halloween with scratches on his face and neck inflicted by the slain girl as she tried to fight him off. The suspect may have experienced social or financial problems leading up to the murder and police say that he might have acted strange or withdrawn from normal life afterwards.

Van Diest died in hospital on Oct. 31 after she was found unconscious and severely injured near the railroad tracks that run through the small town of Armstrong. Police are not revealing the cause of death, but say they believe the attack was random.

The slain teen was last heard from shortly after leaving her family home to meet up with someone. She was dressed like a zombie at the time.

Friends say the last word from Van Diest was a text message to her boyfriend reading, "I'm being creeped."

Van Diest's family says that her boyfriend was the one to discover the teen lying gravely injured in a bushy area.

A little more than a week after the murder, police received a letter from someone claiming to be the murderer and threatening further violence against women. Moskaluk says investigators have yet to determine if the letter is legitimate and have not received any further communication from the author.

Moskaluk says residents of the Okanagan should continue to take extra steps to preserve their safety.

Police have yet to make any arrests in connection with the murder. A dedicated tip line has been set up at 1-888-688-4264.