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MIAMI (CBSMiami) — George Zimmerman says he is auctioning off the gun he used to kill Miami teen Trayvon Martin.

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Zimmerman made the announcement on Wednesday night during a newscast on Orlando’s WOFL television.

The online auction starts Thursday. The opening bid is set at $5,000.

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Zimmerman was asked for his reaction to people who feel the sale is in bad taste. He said those who don’t approve wouldn’t be bidding, so he doesn’t care what they think.

On the web page for the auction, he calls the gun a piece of American history and claims the Smithsonian has expressed interest in acquiring it.

Zimmerman was acquitted three years ago in the shooting death of Martin.

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