Details about two men who 13 years ago may have been involved in the killing of a 57-year-old secretary for the Hawaii State Teachers Association were shared on a recent “Unsolved Mysteries” podcast titled “Hawaiian Homicide.”

Amber Jackson, 57, was last seen alive at her job with the teachers union on Kauai on June 23, 2010. Friends searched for her at her favorite hiking spots and went to her home in Kapahi, where her car was parked in the driveway with her purse and cellphone inside. Jackson’s hiking boots were found in her home. Her body was found in a remote area of Kealia.

The case was the subject of the March 15 “Unsolved Mysteries: Hawaiian Homicide” podcast, in which Kauai Police Department Assistant Chief Bryson Ponce appeared.

Ponce, who has been investigating the case since Jackson disappeared, said two men remain persons of interest in Jackson’s death, but police lack evidence to push the case further to tie them to the crime.

Ponce said on the podcast that Jackson’s home was in a secluded area, and neighbors likely couldn’t hear anything unless they were outside.

Teri Ceplo said she had known Jackson for 10 years, and went to the home when Jackson failed to show up on June 24, 2010, for their regular Friday dinner at a restaurant.

On July 3, 2010, a pig hunter and his dogs discovered Jackson’s body in a Kealia ravine.

Ponce said it appeared to be a “body dump” and that the crime occurred elsewhere. An autopsy revealed Jackson died of blunt force trauma to her head. The side of her face was struck so hard with an object, like a bat or pipe, that it caused an indentation, Ponce said.

“She bled out so much from the head, we couldn’t find any other DNA evidence,” Ponce said.

Ponce recalled seeing her fully clothed body, wearing black socks but no shoes.

Tire tracks but little else were found.

Originally from Riverside, Calif., Jackson moved to the Garden Isle in 2000 from Washington state.

The last person to see her alive was her handyman and ex-boyfriend, who lived in a yurt on the property.

Ponce said that on the night of her disappearance, a responding officer found it odd that the man was washing clothes, sweating heavily and not helping to look for Jackson.

Ceplo said on the podcast that Jackson initially wanted a relationship with the man when they met in 2007, while he was building the yurt as a rental for her. He moved into the yurt in 2008, and Jackson planned to later evict him but could not, Ceplo said. The relationship changed after the pair took a trip to Hawaii island in December 2009 to visit a lettuce farm she owned when she said he suddenly pressured Jackson into having an intimate relationship. Ceplo said she suspects he was manipulating her into allowing him to expand a marijuana growing business to the farm.

The podcast also featured Michelle Stuart, who said a month after Jackson’s death that it dawned on her that suspicious actions by a neighbor of hers coincided with Jackson’s disappearance.

The day Jackson disappeared was the night he did not come home, Stuart said. He claimed he was hiding at Anahola Beach on June 23 because he feared the owner of a boat he hit with his truck was looking for him. But the damage to his truck did not match his story.

Then on July 3, the day Jackson’s body was found, the neighbor asked, “Would you burn my truck down for me?” claiming a local gang owned the boat.

Police later came to Stuart’s home, saying the neighbor reported his truck stolen and asked her to confirm his story that she was with him when it happened.

She said the neighbor admitted to her that he dumped the truck nearby, and it was found with fire damage. She said a large pack of fireworks missing from her house may have been used to torch the truck.

Stuart said her husband, who was paralyzed, had been looking for someone to grow medical marijuana, so the neighbor introduced him to Jackson’s handyman.

Ponce said when he was questioned by police, the neighbor said he was drunk and didn’t remember anything. He denied knowing the handyman, but the handyman said he knew the neighbor.

Ponce said both men are considered persons of interest in the case. They were asked to take polygraph tests, said they would consult with attorneys first, but they never “circled back,” he said.

The handyman continued to live in the yurt until he was evicted, and the neighbor moved to Alaska, according to the podcast.

Jackson’s nephew Matt Alexander said, “We are still grieving our beloved Amber’s senseless and brutal murder and we are not giving up. We know that someone out there has information that could help solve the case.”

The Amber Jackson Justice Group, made up of her family and friends, is offering a $20,000 reward for evidence leading to conviction of the killer.

“The Kauai Police Department remains committed in continuing to seek justice for Amber Jackson and her family and friends,” Ponce said in a news release.

He said he is optimistic that the cold case is solvable, and it might take just one person to come forward with new information or to remember something that was never reported.

To hear the March 15 “Unsolved Mysteries: Hawaiian Homicide” podcast, go to unsolved.com/podcasts/hawaiian-homicide.

Anyone with information is asked to call Kauai police at 808-241-1711 or Crime­Stoppers Kauai at 808-246-8300.