Editor's note: Descriptions of crime in this article may be disturbing to some readers.

UPDATE: Gary Ramirez waived extradition from Maui on Wednesday. He will return to Santa Clara County next week. Read additional information in this story.

The search for the killer in a nearly 40-year-old cold-case murder of a 15-year-old Palo Alto teen has led to the arrest of a 75-year-old man from Hawaii, the Santa Clara County District Attorney's Office announced on Tuesday.

Karen Stitt was last seen by her teenage boyfriend on the night of Sept. 2, 1982, as she walked at night toward a Sunnyvale bus stop. Her naked body was found concealed behind a blood-stained cinder block wall the next morning. She had been sexually assaulted and stabbed 59 times, according to the District Attorney's Office.

Karen had taken a bus from her home in Palo Alto to Sunnyvale to visit her 17-year-old boyfriend that evening. The two met at a 7-Eleven convenience store near the intersection of El Camino Real and Wolfe Road, across the street from the Woolworth Garden Center at 861 E. El Camino Real, at around 8 p.m. or 9 p.m. and purchased drinks, according to a court complaint filed in Santa Clara County Superior Court. They walked north to the Golfland miniature golf course, then walked several blocks northeast to Ponderosa Elementary School.

Around midnight, the boyfriend walked Karen back so she could take a bus home. Worried that he would be grounded for being out after midnight, he went home after watching her walk toward the bus stop, according to the complaint. She was last seen south of the Wolfe Road intersection, walking toward the bus stop on El Camino Real.

The next morning, at approximately 10:45 a.m. on Sept. 3, truck driver Steven Bound was making a delivery to the Woolworth Garden Center and saw what he believed was a nude female lying in the bushes at the base of a cinder block retaining wall along the Garden Center driveway, about 100 yards from the bus stop. He contacted the garden center's manager, who called the Sunnyvale Department of Public Safety.

Arriving officers found Karen stabbed multiple times with her wrists bound behind her back with her shirt. Her jacket was tied around her left ankle, according to the complaint. Medical Examiner Dr. Angelo Ozoa determined she had been stabbed 59 times on her neck, chest, abdomen and back. The neck stab wounds punctured Karen's larynx, trachea and esophagus; 18 chest wounds perforated her heart and 10 perforated her lungs.

The alleged killer's blood and bodily fluid was found on Karen's body; a blood stain alleged to be from the killer also was found on top of the cinderblock wall, just above her body. Kicked leaves and dirt indicated that Karen was still alive when her body was left at the scene, according to the complaint.

Police had no significant leads for decades despite a lengthy investigation until receiving a tip, and DNA evidence linked her alleged killer to the crime. Her boyfriend, who investigators had long considered a suspect in her murder, was cleared based on the DNA evidence, according to the District Attorney's Office.

Sunnyvale Department of Public Safety Detective Matt Hutchison used the tip to determine that Karen's killer was likely one of four brothers from Fresno.

"Genealogy work began in 2019 building the family tree of the perpetrator. In 2021, the genealogist identified the perpetrator as one of four brothers, but couldn’t say which one. That’s when the detective began traditional investigative work to figure out which of the four brothers was the source of the crime scene evidence," Deputy District Attorney Robert Baker said in an email.

Using newspaper notices of family obituaries, databases and social media posts, Hutchison located the family members. Through Facebook, he identified a grandchild of one of the brothers, Gary Ramirez. On April 8 of this year, the detective obtained a sample of the grandchild's DNA, according to the complaint.

Ramirez, 75, was identified as the likely source of blood and bodily fluid left at the crime scene. The Santa Clara County District Attorney's Crime Lab confirmed the identification through DNA evaluation last week, according to the District Attorney's Office.

Ramirez grew up and attended high school in Fresno. He served in the U.S. Air Force in the early 1970s. After leaving the military, he frequented or resided in the Bay Area, San Francisco, San Diego, Colorado and Hawaii, the District Attorney's Office said.

Ramirez was arrested at his home in Makawao, Maui, on Aug. 2. He will be arraigned on murder, kidnapping and rape charges once he is extradited to Santa Clara County. His next court date in the extradition proceedings is this Wednesday, Aug. 10. If convicted, he faces life in prison without the possibility of parole.

"Behind every old murder file in every major police department, there is a person, heartbreak, and a mystery. The mystery of Karen's death has been solved thanks to advances in forensic science and a detective that would never, ever give up," District Attorney Jeff Rosen said in a statement.

On Wednesday morning, Ramirez waived extradition in Maui and will be transported back to Santa Clara County next week by Sunnyvale Department of Public Safety, Baker said.

"We’ve also had contact with people who recognize Mr. Ramirez, as well as family members of unsolved murder victims around the Bay Area who are asking us to look into their cases. Det. Hutchison and the DA’s Cold Case Unit is going to work with relevant agencies to look into them," Baker said.

Meanwhile, Karen's friends and family are processing the arrest of her alleged killer.

Robin Stitt Morris, Karen's aunt, said she was preparing to leave for a vacation and was at her final day of work before heading out of the country when she heard the news.

"When the phone rang I expected some sort of solicitor. I had spoken to Matt Hutchison on prior occasions but didn't immediately recognize his voice. When he identified himself I was absolutely floored when he told me Karen's killer had been found. Matt has been extremely supportive and has been so tenacious in his pursuit of justice for Karen.

"Forty years melted away and the emotions that had been buried all came back. A wound was reopened but somehow I felt relief and peace. Soon, we will be able to write the end to this painful chapter of our lives. I intend to be there when Gary Ramirez is convicted. He stole so much from my family. Karen's death left an indelible scar on our hearts.

"Det. Matt Hutchison's diligence and dedication have gone a long way to ease our pain," she said.

Lori Kinyon, a classmate of Karen's for one semester at Palo Alto High School, said they had a peer counseling class together the year prior to her death.

"I wasn't a friend of hers, just got to know her through the small class setting. She was a 'cool chick' who wore rock t-shirts and had a big smile. I remember her being quite shy in class.

"This story stuck with me throughout the years and was always in the back of my mind. I had a hard time driving by that corner where she was killed on El Camino and Wolfe Road without wondering why and who?

"When the story re-submerged a few years back I was hopeful, but time went by and no leads. This morning when I opened Facebook and saw the story, I couldn't believe what I was reading!

"I'm happy her family can finally get the justice they deserve. I'm not sure who the tipster is and why they finally came out to point the finger after all this time, but Thank God the words got out! The family needs this, I know — trust me — I know," Kinyon, whose father, Andrew, was murdered in San Francisco in 1972 and whose case remained cold for 50 years, said in an email.

Arresting Ramirez took months of planning and was a coordinated effort involving Santa Clara County, Maui and federal law enforcement authorities, the District Attorney's Office said. It was funded largely by a grant awarded to the office in 2021 by the U.S. Department of Justice to investigate and prosecute cold cases.

Anyone with information about Ramirez is encouraged to contact Rob Baker, a cold case prosecutor at the District Attorney's Office, at rbaker@dao.sccgov.org.