On Aug. 12, 1996, the body of 18-year-old Glenn Guerrero was discovered off a dirt road in Keaau.
Police said he had been fatally shot, but his killer was never found.
On Friday, Big Island authorities renewed their plea for leads in the cold case, saying that witnesses had spotted Guerrero earlier in the day in the passenger seat of a pickup leaving the area. Detectives have never been able to identify the pickup truck's driver.
"Previous leads have since been exhausted and, despite the advances in forensic science technologies, this murder investigation remains unsolved," said Police Lt. Gregory Esteban, in a news release.
"We're still hopeful that with the passage of time and changes in relationships, individuals may be more willing to come forward with useful information that may lead to a resolution to this investigation. The Hawai'i Police Department remains committed in its efforts to revisit and re-evaluate this and other unsolved homicides and to bring closure for the families of the victims."
Anyone with information on the case is asked to call Detective Derek Morimoto at 961-2380. He can also be reached by email at email@example.com.