Researchers working for the Defense Advanced Research Projects Agency (DARPA) of the US Department of Defense have come up with a technology that's as brilliant as it is creepy - homing bullets that can self-steer their way into the flesh of a target. Watch above to see how even an amateur shot can hit a moving target with one of these things during a round of live-fire tests. While the technology has been in development for a few years now, this is their most successful test run so far.

The aptly named Extreme Accuracy Tasked Ordnance - or EXACTO - program that birthed this technology says they were designed to give difficult, long-distance shots a higher success rate, especially if the targets happen to be constantly moving or trying to evade getting hit. They say they can work over a distance of up to 2 kilometres.

"This video shows EXACTO rounds manoeuvring in flight to hit targets that are moving and accelerating," the team says at their YouTube page. "EXACTO's specially designed ammunition and real-time optical guidance system help track and direct projectiles to their targets by compensating for weather, wind, target movement and other factors that can impede successful hits."

The technology works by having the sniper mark a target with a laser light, and each 10-cm (4-inch) bullet has an optical sensor embedded in its nose that can detect this laser, which means it can send information back to the shooter about its position relative to the laser target. This allows the shooter to operate tiny motors inside the bullet to alter its path on the fly. "We can make corrections 30 times per second," one of the team, Red Jones, told the BBC. "That means we can over-correct, so we don't have to be as precise each time." 

The researchers say by making bullet technology more accurate, it will cut down on unnecessary casualties in the field.

But the one major concern with the technology - and it's a big one - is if it gets into the hands of terrorists. "The public may be uncomfortable with the implications of people being able to use this without needing to have a sight line to the target - you could see this having terrorist uses," Elizabeth Quintana, senior research fellow at the Royal United Services Institute think-tank, which is not involved in the research, told the BBC. "There's talk of selling to recreational hunters, but I would imagine the authorities would want to limit the public's access to this kind of technology. It would be useful for law enforcement - particularly in hostage situations."

Criminals beware, I guess?