STOCKTON, Calif. (AP) - The mother and sisters of a girl whom authorities think was killed more than 27 years ago by California's notorious "Speed Freak Killers" are suing San Joaquin County officials over the handling of the 16-year-old's exhumed remains.

Joan Shelley and her two surviving daughters filed a federal lawsuit in Sacramento on Monday alleging that the backhoe employed by Sheriff Steve Moore caused JoAnn Hobson's bones to be chopped up and co-mingled with those of other victims whose remains were recovered in Linden last year.

The lawsuit, first reported by The Stockton Record, seeks unspecified damages for negligence and emotional distress.

A spokesman for the sheriff's office did not immediately return a call seeking comment.

Based on complaints Shelley voiced earlier, the sheriff has asked the FBI to handle the search for additional victims.

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