An honest mistake in California has become a serious situation.

The Los Angeles Times reported that a sheriff's deputy on Orange County "lost his AR-15 assault rifle Tuesday after placing it on the trunk lid of his patrol car and driving off."

The gun was inside its case atop the trunk of his car when the deputy "became distracted and drove off." The deputy reportedly didn't notice the weapon was missing for eight hours.

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KABC added that authorities manned with bloodhounds looked for the rifle and found nothing. 

Officials told KABC that the black Colt AR-15 has a 20-inch barrel. Its serial number is A0091856. The gun was loaded with three magazines when it was lost.