Using cheap magnet, hacker beats protections on a "smart" handgun.

This week the world’s elite hackers are gathering in Las Vegas for Def Con, the largest underground hacking event of the year.

The BBC’s North America technology reporter met a hacker who had circumvented protections on a handgun designed to make it impossible for unauthorised people to shoot.

This week BBC News is taking a close look at all aspects of cyber-security. The coverage is timed to coincide with the two biggest shows in the security calendar - Black Hat and Def Con.

28 July 2017