Media playback is unsupported on your device Media caption Trayvon Martin: Death weapon up for auction

A gun used to shoot dead unarmed Florida teenager Trayvon Martin is to be auctioned by the man who shot him, George Zimmerman.

Mr Zimmerman, a neighbourhood watchman, was cleared over the death of the 17-year-old in February 2012 after saying he acted in self-defence.

He said he was selling the gun partly to raise funds to fight "Hillary Clinton's anti-firearm rhetoric".

The Martin family would not "comment on the actions of that person", they said.

"The Trayvon Martin Foundation is committed to its mission of ending senseless gun violence in the United States," his family said in a statement to media in Florida.

"This election season, we are laser focused on furthering that mission."

When asked by Florida television channel WOFL what he would say to people opposed to the sale, Mr Zimmerman said: "They're not going to be bidding on it, so I couldn't care less about them.''

Analysis - Nick Bryant, BBC North America correspondent

Few cases in recent years have been more racially sensitive or led to such an anguished national conversation as the killing of Trayvon Martin. It sparked demonstrations around the country, prompted President Obama to remark that if he had a son, he'd have looked like the black teenager and brought about the first use on social media of the hashtag "Black Lives Matter."

So the decision of the former neighbourhood watchman, George Zimmerman to put the gun he used up for auction not only seems extraordinary but also cruel and callous - especially since he refers to the weapon on the online site as an "American icon."

This is not the first time that Zimmerman has sought to cash in on his notoriety. His first painting of an American flag, emblazoned with the words "God One Nation with Liberty and Justice For All," sold on eBay for the staggering sum of $100,000. But it did not impress critics, who called it "primitive" and "appalling."

Harsher language will no doubt be used to describe the sale of the pistol that killed Trayvon Martin.

The one-day online auction opens at 11:00 EDT (15:00 GMT) on Thursday. The opening bidding price for the 9mm pistol is set at $5,000 (£3,464).

On the auction site, Mr Zimmerman refers to the gun as an "American icon", and says it was recently returned to him by the US Department of Justice.

Image copyright Getty Images Image caption George Zimmerman said he was assaulted by Trayvon Martin and acted in self-defence

Image copyright Getty Images Image caption Mr Zimmerman said the gun was recently returned to him

Florida police did not arrest Mr Zimmerman for six weeks after the shooting in Sanford, Florida, provoking mass rallies in Florida and throughout the US.

Police justified their decision not to detain him by citing the state's controversial "stand your ground" law, which allows a citizen to use lethal force if he or she feels in imminent danger. Police initially said the law prevented them from bringing charges.

Profiles: Trayvon Martin and George Zimmerman

Mr Zimmerman's defence said Trayvon Martin had punched their client, slammed his head into the pavement and reached for Mr Zimmerman's gun. Prosecutors accused Mr Zimmerman of telling a number of lies.

The case led to protests in several cities in the US and to the birth of the Black Lives Matter movement.

Mr Zimmerman has generated headlines several times since his closely watched trial.

He was arrested and charged with domestic aggravated assault against his girlfriend in 2013 and 2015 but both times the charges were dropped.

In 2015 he was involved in a road rage incident in which a motorist fired a bullet into Mr Zimmerman's car. He sustained light injuries from flying glass.