HONOLULU (TCN) — Authorities recently arrested a man at a nursing home on suspicion of sexually assaulting and fatally strangling a teen at a high school nearly five decades ago.
According to Honolulu Police Lt. Deena Thoemmes, on the morning of March 21, 1977, officers responded to McKinley High School to a report of a possible homicide. Police discovered 16-year-old Dawn Momohara on the second floor of the English building partially clothed with an orange cloth wrapped “tightly” around her neck.
Officials pronounced Momohara dead at the scene and determined she had been sexually assaulted. Police recovered her purse, shorts, and other evidence. Thoemmes said an autopsy later revealed Momohara had died of asphyxiation due to strangulation and sustained injuries around her neck where the orange cloth was used to strangle her. Investigators believe she was killed during after hours at the school.
The morning before she was killed, Momohara allegedly received a call from an unknown man. The victim reportedly told her mother she was going to go shopping with some friends, and that was the last time she saw or heard from her daughter.
According to police, investigators collected scrapings from the scene and semen. As part of the investigation, detectives interviewed friends of the victim. A witness reportedly said he and his girlfriend saw a car and a man near the English building. The man walked out, and the witness allegedly circled the vehicle, but they had left.
Thoemmes said police had a sketch drawn up, but they were unable to find any leads at the time.
On March 28, 1977, detectives interviewed Gideon Castro. He reportedly told authorities he met Momohara at a school dance in 1976, the year he graduated from the high school. Gideon Castro claimed he and his brother, William Castro, were both friends with the victim. According to police, Gideon Castro told detectives he last saw Momohara at a carnival, and they spoke for around 15 minutes.
William Castro allegedly said he last saw the victim walk past his home, and he offered a ride, but she refused.
Decades later, in 2019, investigators re-examined the case and submitted a request to process items from the scene. The following year, police said investigators created a DNA profile from the recovered semen. According to Thoemmes, in 2023, investigators received information that either Gideon Castro or his brother William Castro could be suspects in the case.
Detectives reportedly traveled to Chicago where William Castro had been living and obtained a DNA sample from one of his grown children to compare it to the DNA found at the scene. As a result, they ruled William Castro out as a suspect.
Police said authorities located Gideon Castro in Utah and also obtained a DNA sample from his son. Investigators concluded the DNA found at the scene was a match with Gideon Castro and identified him as the primary suspect in the cold case.
Officers arrested Gideon Castro at a nursing home in Utah on a charge of second-degree murder. He will be extradited back to Honolulu to face the charge.
