CBS

Elon Musk is joining a group of prominent robotics and artificial intelligence researchers in calling on the UN to prohibit the development and use of robotic weapons.

The CEO of Tesla Motors and SpaceX joined 116 specialists from 26 countries warning in a letter that the use of autonomous weapons could usher in the "third revolution in warfare," The Guardian reported Sunday. The UN recently voted to begin formal discussions on such weapons, including drones, tanks and automated machine guns.

"Once developed, lethal autonomous weapons will permit armed conflict to be fought at a scale greater than ever, and at timescales faster than humans can comprehend," the letter warns. "These can be weapons of terror, weapons that despots and terrorists use against innocent populations, and weapons hacked to behave in undesirable ways.

"We do not have long to act. Once this Pandora's box is opened, it will be hard to close."

Research in AI -- a term used for the ability of a machine, computer or system to exhibit humanlike reasoning-- has been dominated by large tech companies such as Google and Facebook. That work has led to everyday applications such as screening out spam and finding friends' faces in digital photos.

But there's a darker side looming: autonomous weapons, including unmanned planes, missile defense systems and sentry robots.

Musk may be a techno-optimist when it comes to solar power, space exploration and electric cars, but he continues to express his concerns that superintelligent machines might one day pose a threat to human existence.

Though many futurists envision an application of AI more beneficial for humans, Musk has voiced his apprehensions on several occasions. In 2014, he told CNBC that he worries unrestrained AI could breed an uncontrollable threat to humans like that depicted in the 1984 movie "The Terminator."

Tesla didn't immediately respond to a request for comment.

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