FULLERTON (CBS) — The Orange County District Attorney is halfway through his investigation into the death of 37-year-old Kelly Thomas.

Tony Rackauckas’ office is looking into whether six Fullerton police officers used excessive force when they arrested Thomas at a bus depot on July 5.

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Thomas, who suffered from schizophrenia, died five days after his arrest.

Rackauckas’ office has talked to 100 witnesses so far, but investigators are still waiting for a toxicology report.

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The Fullerton City Council also approved a contract to hire independent investigator Michael Gennaco.

Fullerton’s police chief, Michael Sellers, was placed on paid medical leave shortly after Thomas’ death.

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