A southern New Jersey man whose unsuccessful bid to kidnap his girlfriend ended in the death of a retired police officer has lost his bid to have his prison sentence reduced.

Cumberland County prosecutors say a state appellate court recently rejected Christopher Robinson's request. The Millville man had claimed his sentence -- 30 years in prison without parole -- was excessive.

Robinson was sentenced in February 2011, shortly after pleading guilty to murder and attempted kidnapping.

Robinson was trying to stuff his girlfriend into the trunk of his car at a convenience store in February 2007 when 51-year-old Carmen DeGregorio intervened.

DeGregorio, who served on the Millville force, freed the woman and fought off Robinson, who then ran him down. DeGregorio suffered serious head injuries and died two days later.

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