A video uploaded to YouTube early Friday reveals an Amazon Prime Drone delivering a small box—reportedly containing sunscreen—in Southern California earlier in the week.
On Monday, tech news GeekWire reported on the flight based on tweets and a short Periscope video by Jason Johnson, who describes himself on Twitter (twtr) as a home automation expert. Johnson attended the MARS 2017 conference, an invite-only event in Palm Springs, where the flight took place.
MARS 2017 bills itself as an exclusive venue for professionals in and fans of robotics, home automation, artificial intelligence, and space exploration. It’s also where Amazon chief executive officer Jeff Bezos piloted a 13-foot robot on Monday.
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Amazon Prime drones have popped up here and there—but only in carefully-controlled environments. The first public showcase occurred during an episode of 60 Minutes four years ago. More recently, an Amazon (amzn) drone made a cameo appearance in an Amazon Super Bowl commercial. Amazon also brought the drones to the annual SXSW tech fest in Austin this month, although it did not run live demos.
As Fortune’s Jonathan Vanian has reported, Amazon has made some test deliveries in the U.K., and last year won a patent for an “airborne fulfillment center.” That could help Amazon ship deliveries via drone in coming years.
But while Amazon, Facebook (fb), and other drone proponents forge ahead, the U.S. Federal Aviation Administration is restricting the flights of unmanned aircraft for safety reasons. Last June, the FAA issued rules restricting the altitude and hours of use for commercial drones.