Details of Disappearance
Koja was last seen in Oahu, Hawaii on June 9, 1997, which was her birthday. She left her home on Mie Place to take her usual early morning walk at 3:00 a.m. She typically walked to California Avenue and a mile past Leilehua High School to the Wahiawa Hongwanji Mission before turning back.
She never returned from her walk and has never been heard from again. Koja left behind her four dogs and her husband, who needed her assistance with most daily tasks because he had arthritis.
Neighbors heard screams in the area at about 4:00 a.m., but they thought it was just rowdy teenagers and did not investigate. At 7:10 a.m., a janitor at Leilehua High School found a substantial amount of blood on a concrete walkway outside a classroom. He believed it was a prank and hosed down the walkway.
A witness who saw him cleaning up called the police after hearing Koja was missing, and police searched the area. They found a trail of blood leading to a dumpster behind the school.
Koja's headphones and pepper spray can were in a trash can at the school bus stop. A school employee said he found them on the grounds and threw them away. A piece of Koja's dental bridgework was in front of the school, and broken parts of eyeglasses matching Koja's prescription were recovered also.
On June 12, Frank Janto voluntarily went to the police and said he wanted to discuss Koja's case. He has a substantial prior criminal record, beginning as a juvenile, for offenses such as car theft, child molestation, disorderly conduct and assault. One of his convictions was for beating a 65-year-old Vietnamese woman while she was walking in Honolulu; she was seriously injured and had to be rescued by the police.
Photographs of Janto are posted with this case summary. He confessed to attacking Koja while under the influence of cocaine and crystal methamphetamine. He said he ambushed her while she was walking, beat her to death and dragged her body to the trash bin.
Janto, accompanied by law enforcement officers, went to Leilehua High School and he told them how the murder had taken place. By then, the trash bin had been emptied and its contents had been hauled away and incinerated.
Janto was convicted of second-degree murder in Koja's case in April 1998. He was sentenced to a minimum of 75 years in prison, which is believed to be the longest minimum sentence the state parole board has ever handed down.
In 2008, Janto was charged in the 1987 death of Rose Chiquita, who was beaten and stabbed to death at a Hilo, Hawaii service station. Both Chiquita and Koja were older women who were attacked while walking alone early in the morning. Authorities noticed similarities in their cases after Janto's conviction in Koja's presumed death. Janto pleaded guilty to second-degree murder in Chiquita's case in October 2008 and sentenced to life in prison.
Koja's remains have never been found and are believed to be unrecoverable. Foul play is suspected in her case due to the circumstances involved.