Researchers at the University of Texas say they\'ve demonstrated the Global Positioning System signals of unmanned aerial vehicles can be hacked. Engineering Professor Todd Humphreys and his students were invited by the U.S. Department of Homeland Security to attempt the demonstration in New Mexico in late June. Using hardware and software they developed, the UT team repeatedly took control of navigational signals going to a small but sophisticated UAV, a university release reported Friday. Known as \"spoofing,\" the technique creates false GPS signals to trick the vehicle\'s GPS receiver into steering a navigational course chosen by the outside hacker. Humphreys said his research team wanted to demonstrate the potential risks associated with spoofing as the Federal Aviation Administration considers mandated rules that would allow government and commercial drones in U.S. airspace by 2015. \"We\'re raising the flag early on in this process so there is ample opportunity to improve the security of civilian drones from these attacks, as the government is committed to doing,\" Humphreys said.