Details of Disappearance Santoso was last seen at his apartment during the evening of February 19, 2001. The apartment is located at at the Four Cedars Apartments in the 10000 block of northeast 117th Court in Kirkland, Washington.
Other residents of the apartment complex reported hearing breaking glass, banging and thumping, and several screams at around 10:45 p.m. the day Santoso disappeared, followed by the sound of a car speeding away at approximately 11:00 p.m.
Later, the front door to the apartment was found open and a cinder block had been thrown through one of the windows. Police found a great deal of blood blood and signs of a burglary inside the residence, and more blood outside the apartment building, but there was no sign of him.
His car, a dark green 1999 Ford Mustang convertible with the Washington state license plate number 146 KYB, which is pictured with this case summary, was later located at the Seattle-Tacoma International Airport parking garage. The parking receipt was time-stamped 11:51 p.m.
The vehicle had a substantial amount of Santoso's blood inside and a bloody palm print on the outside. There is no indication that Santoso took a flight out of the airport, and his passport has not been used since his disappearance.
Later, a knife covered with Santoso's blood was found in Newcastle, Washington, off Interstate 405.
A month before his disappearance, Santoso filed an assault complaint with the police. He claimed he had been choked, bound with duct tape, and threatened with a gun and a syringe full of drain cleaner by Kim Heichel Mason, a professional kickboxer who had been his friend.
A photograph of Mason is posted with this case summary. He is also known as Hiiro Takashi Riser and/or Brian Allen Mason. Santoso claimed Mason demanded he write a check for $700 to pay a drug dealer before he eventually released him.
Mason was charged with first-degree kidnapping and robbery in connection with the incident. He admitted to choking Santoso, but said it was to ward off unwanted sexual advances. Santoso, who is bisexual, told police that he and Mason had once had a sexual relationship. Two other witnesses confirmed it, but Mason denies it.
Santoso got a restraining order to keep Mason away from him after the assault. He was afraid for his life after reporting Mason to the police, and slept with a hammer in his bedroom and a knife under the couch. He told his friends that he wanted to move to Portland, Oregon to get away from Mason.
In April of 2001, two months after Santoso's disappearance, Mason was charged with first-degree murder in connection with his case.
Authorities say Mason broke into Santoso's apartment, stabbed him to death, disposed of the body, and left Santoso's car at the airport to make it appear as if he had left the country. The motive was probably to prevent Santoso from testifying against him in connection with the assault and robbery.
Mason's girlfriend, Marina Madrid, says she picked Mason up from the Seattle-Tacoma International Airport the night Santoso disappeared, and noticed that he had a bandage wrapped around his thigh. When she asked him about it, he answered, "Santos is no longer a problem." She witnessed him dispose of bloodstained clothing and a bloody knife.
Madrid claims Mason disappeared for three days after Santoso vanished, and when he returned, he confessed to her that he had killed Santoso and decapitated the body to make identification more difficult before he disposed of it in an unknown location. He said he had accidentally stabbed himself in the thigh during the attack.
Police had blood and DNA evidence they said proved Mason's guilt, including some of his blood in Santoso's car. Santoso's blood was also found in the passenger compartment Madrid's car. Madrid originally provided an alibi for Mason, and changed her story only after police offered her immunity from prosecution for any role she might have played in Santoso's murder.
Mason's blood and fingerprints were not found in Santoso's apartment, though they were in Santoso's Mustang. The bloody shoe prints inside the apartment were too big to be from his feet. In addition, the palm print in blood found on the outside of Santoso's car was not Mason's.
Nonetheless, Mason was convicted of Santoso's murder in June 2003. He was sentenced to life in prison without the possibility of parole. He maintains his innocence in Santoso's disappearance.
Santoso remains missing. He is an Indonesian immigrant who moved to the United States about five years prior to his disappearance. He has no family members in the States, but was helping to support a large family back in Indonesia. He was employed as a nursing assistant in 2001.
Foul play is suspected in his case due to the circumstances involved.
- Kirkland Police Department
Updated 2 times since October 12, 2004. Last updated September 27, 2007; date of birth added, distinguishing characteristics updated.