The emotional pain felt by friends over Amber Ellis Jackson’s death deepens as the homicide case remains unsolved on Kauai.

"It really definitely doesn’t get easier. It’s very depressing. I think as each year passes, it gets worse instead of better," Teri Ceplo of Kapaa said in a phone interview.

Jackson’s friends want the Kauai Police Department to seek outside help with the investigation five years after her death. "We’re really convinced without outside help, this case isn’t going to be solved," Ceplo said.

Police spokeswoman Sarah Blane said the department has had outside expertise throughout the investigation "including investigative specialists, forensic analysts and forensic/DNA testing."

"While we are unable to release details of the ongoing investigation, Amber Jackson’s homicide remains a top priority for both the Kauai Police Department and the Office of the Prosecuting Attorney," said Blane in an email.

Jackson, 58, of Kapahi disappeared on June 23, 2010. Ceplo said she had planned to meet Jackson and other friends at an Italian restaurant in Kapaa for dinner but Jackson never showed up.

A pig hunter found Jackson’s body in a remote valley in Anahola on July 3, 2010. An autopsy found that she sustained injuries caused by an assault. The area where her body was discovered was described to be one of the spots where Jackson hiked.

Friends described Jackson, who worked as a secretary for the Kauai office of the Hawaii State Teachers Association, as a sweet woman who loved the outdoors. "She loved hiking," Ceplo said.

Her hiking boots were still in her home at the time of her disappearance. Jackson’s car was found parked in the driveway at her home, with her purse and cell phone inside the vehicle.

Jackson’s friends created the Amber Jackson Justice Group to help law enforcement and the prosecutor’s office on the case.

The group is offering a $20,000 reward for information leading to the arrest and conviction of the person or people responsible for Jackson’s murder.

Anyone with information on the case is urged to call police at 241-1711.