ROHNERT PARK (CBS SF) — Sonoma County sheriff’s detectives were searching for a Bose speaker box that belonged to a slain Cotati teenager whose body was found in a shallow grave at Sonoma State University last week.

The Sheriff’s Office said that Kirk Kimberly was believed to have been carrying the speaker box in his backpack at the time of his stabbing death.

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Kimberly, 18, was reported missing Oct. 17. His body, with multiple stab wounds, was found on Nov. 2 in a secluded area of the campus by a landscaper who was clearing brush.

Detectives say they have thus far not found that he had any link with the university or its students other than where his body was found.

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The Sheriff’s Office said the speaker box was a Bose Soundlink III. Anyone who has come across such a box, or whose children may have found one, has been asked to please contact Sheriff’s Detective Horsman at (707) 565-2185.

Detectives were also looking for Kimberly’s mountain bicycle, which he was riding when he was last seen leaving his Cotati home. The bicycle is a white 2011 Cannondale Quick CX 3 with recently installed road tires that have reflective material on the sidewalls.

Detectives said last week that they preliminarily believe the homicide was not a random act of violence but was an isolated incident.

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