PORTLAND, Ore. (KOIN) — A Clark County jury has found suspected serial killer Warren Forrest guilty of killing a Portland teenager nearly 50 years ago.

The jury concluded DNA evidence tied Forrest to the murder of 17-year-old Martha Morrison in 1974. He dumped her body in a remote part of Clark County.

Forrest has long been suspected of killing seven women and teenagers but was only convicted of one killing until now.

Court documents say Forrest told the prison therapist his first attack was against a woman in Texas while he was in the Army around the age of 20.

Forrest also made problematic statements to the parole board, saying that he attacked women to cope with feelings of worthlessness and hopelessness.

During the trial, Norma Lewis testified to surviving a kidnapping attack at the hands of Forrest when she was a teenager. Although it took 50 years for this conviction, she tells KOIN 6 News the guilty verdict came in less than two hours – with the jury determining DNA evidence found on a weapon Forrest used to attack another woman tied him to Morrison’s murder.

“So many of those young girls, their parents died without knowing what happened to their daughters,” she said. “I don’t care about anything else, I just want answers for those families that don’t know what happened to their loved ones.”

While Morrison’s brother says he is overjoyed to see justice for his late sister, he says there is still work to be done for the other suspected victims.

“This isn’t about just killing Martha, it’s about all the rest of us that have had to deal with this for years and years. That’s hard on people,” said Michael Morrison.