A 66-year-old man was arrested in a Utah nursing home this morning in connection with the March 21, 1977 fatal strangling of a 16-year-old McKinley High School student whose body was found in a campus building.

Dawn Momohara, then a sophomore at McKinley, was sexually assaulted and strangled to death 47 years ago. Her body was found on the second floor of the English building shortly after 7:30 a.m. Hawaii time.

Today at 7:40 a.m. Hawaii time, the Mill Creek Investigations Unit of the Unified Police Department of Greater Salt Lake arrested Gideon Castro, 66, on suspicion of second-degree murder, Honolulu Police Department Lt. Deena Thoemmes told reporters at a news conference.

On March 21, 1977, Momohara was found lying on her back and partially clothed. She was pronounced dead at the scene. Officers found her purse, slipper, shorts and other evidence.

An orange cloth was tightly wrapped around her neck.

The morning before she was killed, Momohara got a call from an unknown man. Later that day she told her mother that she was going to Ala Moana Shopping Center with some friends.

“That was the last time that Dawn’s mother saw or heard from her daughter,” said Thoemmes.

An autopsy determined Momohara died of asphyxia due to strangulation and the manner of her death was homicide. Momohara had injuries to her neck where an orange cloth was used to strangle her.

The city Department of the Medical Examiner determined she also suffered injuries consistent with sexual assault.

Scrapings recovered from the scene and during the autopsy were examined and determined to be seminal fluid with the presence of sperm. DNA surreptitiously acquired from Gideon Castro’s son matched a sample found on Momohara’s shorts.

HPD investigators flew to Utah and covertly acquired a DNA sample from Gideon Castro that matched the evidence found on Momohara’s shorts.

On March 28, 1977, detectives interviewed Castro, who was later identified as a suspect.

He told police he knew Momohara since late 1976, when he met her at a school dance. Gideon graduated from McKinley in 1976 and told police that Momohara was friends with him and his brother William Castro.

He said Momohara used to call him when he was still in high school and that he last saw her at the McKinley carnival in February of 1977 where they talked for about 15 minutes.

He told her he was in the U.S. Army Reserve and had come home to Honolulu. William Castro was also interviewed by police and told detectives that he met Momohara at a school dance with his brother Gideon.