Stevie Marie Vigil of Commerce City is accused of buying the gun from a weapons dealer and giving it to Ebel, who could not purchase his own gun because he was a convicted felon, according to the Colorado Bureau of Investigation.

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The world desperately needs the final agreement to ensure that no country or arms dealer will sell weapons, munitions or related equipment to governments, companies or armed groups where there is a substantial risk of those arms and ammunition -- ranging from AK-47s to bombers -- being used for atrocities or violent abuse.

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The US has touted the successes it has had - such as last month's international sting operation which prosecutors say caught an arms dealer hoping to import weapons just as Mr Graham described.

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Martin Bale, a registered firearms dealer in Cardiff, said some gun owners did not register their weapons following the introduction of tighter legislation in the 1990s.

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