ONTARIO (CBSLA.com) — Investigators said they found human remains in the backyard of an Ontario home during a search for a missing Laguna Hills truck driver.

Police said they discovered “charred or burnt human remains” during a four-day investigation at a residence in the 1700 block of South Palm Avenue.

The San Bernardino County Coroner’s Office will now determine if the remains, which included bone fragments and teeth, belong to 28-year-old Oscar Javier Contreras Escobar, who has been missing since August 2012, according to Sgt. David McBride of the Ontario Police Department.

Officials have long believed Escobar, who was last seen in Fontana, may have been a victim of foul play.

Detectives were originally drawn to the Inland Empire because of “suspicious activity” on Escobar’s bank card, but other unknown leads brought them to the home in Ontario.

Authorities said they questioned two men and a woman who were in the house when it was searched, but haven’t made any arrests.

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