Successful trials of a newly developed handgun that can only be fired by its owner have been completed in the US.
Staff from the R&D department of the New Jersey Institute of Technology (NJIT) have integrated technology called Dynamic Grip Recognition into a standard handgun.
Sixteen sensors built into the handgun measure the user's hand position and the force of the trigger pull before deciding whether or not to discharge.
"We've only just begun and we're pleased to say that we're getting 90 per cent reliability when scanning users," said Donald Sebastian PhD, senior vice president of R&D at NJIT.
"The dynamic biometric depends on both physical markers and behaviour. This is about who you are and how you do something."
Development work on the smart gun began in 1999, and the state of New Jersey passed a law in December 2002 requiring all guns sold in the state to be 'smart' within three years of them becoming commercially available.
So far $2m has been spent on the project.
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