VANCOUVER, Wash. (KOIN) — A document from the Washington State Crime Lab talks about “DNA,” “skeletal remains” and a blood “stain on the grip of (an) air pistol.” Then the document delivers a bombshell: the blood stain belongs to Martha Morrison.

Martha Morrison was 17 when she disappeared from Portland in 1974. Her body was found in a remote area of Clark County along Dole Valley Road next to the body of Carol Valenzuela, a young wife and mother.

For decades, investigators believed the blood stain on the pistol belonged to the woman who was kidnapped from Portland then brutally attacked, raped and buried alive at Lacamas Lake by convicted killer Warren Forrest.

Forrest, long suspected of being a serial killer with at least 6 victims, admitted attacking the woman at Lacamas Lake and said he used that air pistol to shoot “hand honed darts” into her.

According to the Washington State Crime Lab, the chances the DNA test linking the 2 cases are wrong is 1 in 30 billion.

Sgt. Duncan Hoss with the Clark County Sheriff’s Major Crimes team said it is a mindboggling result after so much time.

“The Cold Case Unit started examining all the evidence and they got that air pistol out and noticed there was some blood on the handle and sent it off for DNA testing. Now everyone assumed it was related to his prior convictions, but when we got the lab results back we found out it wasn’t related to prior convictions, it was to an unsolved homicide in 1974,” said Hoss. “Absolutely boggling.”What this means

Warren Forrest has been in prison since 1979 for the murder of Krista Blake near Battle Ground, but he has long been suspected of being a serial killer with at least 5 more victims.

Since the DNA shows the blood is Martha Morrison’s, Clark County detectives say it not only conclusively ties Warren Forrest to one of those 5 murders he has consistently denied committing, it also proves Forrest killed Carol Valenzuela.

A 43-year-old crime scene map shows their bodies were found together in a remote part of Clark County.His most recent parole hearing

In mid-July, Warren Forrest tried to convince the parole board he was no longer a danger. He blamed overwhelming stress in his life for the 1974 abduction and murder of Krista Blake near Battle Ground, the abduction and attack on 15-year-old Norma Countryman, and the brutal attack on the woman at Lacamas Lake.

“I picked up a young lady with a ruse of offering her a job and drove her to a secluded area and sexually assaulted her, raped her,” Forrest told the parole board in July.

During that hearing, the parole board hinted detectives were close to a breakthrough on other cases connected to Forrest: Gloria Knutson, Barbara Ann Derry, Jamie Grissim, Valenzuela and Morrison.

Parole Board Chair Kecia Rongen asked the 68-year-old Forrest about a June visit from the Clark County Sheriff’s Office. At that time, investigators provided Forrest with a document.

“You’re suspected in at least — what is it? — 1, 2, 3, 4, 5 other abductions and/or murders?” Rongen asked.

“Yes, ma’am,” Forrest replied.“Are you denying them?”“Yes, ma’am.”

Forrest’s lawyer re-iterated he was denying his involvement.

Hope for Jamie Grissim’s family

The breakthrough is giving hope to Starr Lara, the sister of Jamie Grissim, who detectives believe was Warren Forrest’s first victim.

The DNA breakthrough is “huge. It’s 40 some years in the making,” she said.

She disappeared one day after leaving Fort Vancouver High School in 1971 and her body has never been found. But a school ID card was found along Dole Valley Road, just several miles from where the bodies of Martha Morrison and Carol Valenzuela were found.

“When Jamie first disappeared, I’d get her birthday presents and Christmas presents and write her letters, because I wanted her to know I didn’t forget,” Lara told KOIN 6 News. “Then when these 2 girls were found, I knew she wasn’t coming back.”Filling in the blanks

The sheriff’s office is still trying to fill in blanks in the case, which is why they want to find Martha Morrison’s boyfriend.

The couple was living in North Portland when Martha, then 17, disappeared.

Detectives believe he was about the same age.

It was reported that the couple had a disagreement and he was going to move out and leave. Authorities said he’s not a suspect.

“He was a black male and she was a white female. Back in 1974 that wasn’t as common as it is today and might have stood out in somebody’s memory, a neighbor.” Sgt. Duncan Hoss said. “He worked at the shipyards. A welder or a grinder — Vancouver shipyards — Portland shipyards.”

While authorities don’t even know his first name, they think he might be able to answer questions about the day Martha disappeared to make sure Forrest answers for what happened to her so many years ago.The next legal step

The Clark County prosecutors have to decide if there’s enough evidence to charge Warren Forrest with the murders of Martha Morrison and Carol Valenzuela.

Detectives said they don’t have enough evidence to charge Forrest with the murders of the other 3 women he’s suspected of killing.

Starr Lara is hoping they can make some kind of deal with him to convince him to reveal where Jamie’s body is buried. But what that kind of deal looks like remains to be seen.

However, prosecutors could allow Forrest to still go before the parole board instead of life behind bars and hope the parole board continues to keep him locked up.