At the same time, North Korea also has been developing its own drone weapons. A North Korean defector claimed earlier this year that Pyongyang may have hundreds of attack drones capable of unleashing biological and chemical weapons.
Analysts say the drone swarms by South Korea could be used to target a leadership convoy or limousine, including one carrying North Korean leader Kim Jong Un. The swarms also could utilize "kamikaze" style, meaning the weapon self-destructs when hitting targets.
Indeed, there were rumblings in September that South Korea was forming a "decapitation unit" to target the hermit regime's leadership, according to The New York Times. The report followed the North's sixth nuclear test.
"You could use them for assassination strikes or you could use them for preventative strikes," said Harry Kazianis, director of defense studies at the Center for the National Interest, a U.S think tank.
Added Kazianis, "If you build them cheap enough and build enough of them you almost have a situation like it's the 'Terminator' — basically having drones and robotic weapon systems. So this is why the United States and countries like South Korea, who have the money and the R&D capabilities, are investing in them."
Still, the dronebots probably wouldn't have weapons as powerful as large unmanned aerial vehicles, such as the U.S.-made Predator or Reaper. That said, they could conduct surveillance and then disable the North's ballistic missiles on transporter-launcher vehicles or take out rocket or artillery batteries.
"North Korea is believed to have hundreds if not more well-defended artillery units," said John Schaus, a defense expert and fellow in the International Security Program at the Center for Strategic and International Studies, a Washington think tank.
Schaus said the North's military has artillery placements that are sometimes dug into mountains so they can retreat back for protection. However, with a swarm of drones the South Koreans could identify those units as they come out and strike them.
"What we're hearing about is still notional," said Cheng. "We don't have any evidence they've created it yet. But we've seen what drones can do."
For one, the U.S. has been conducting research and development on drone swarms for many years. One project the Pentagon is planning to test is "aircraft carriers in the sky" that would launch and retrieve swarms of drones using a transport aircraft.
China and Israel also have their own programs focused on drone swarm technology.
Experts say the drone swarms also would be more difficult to detect than most combat aircraft.
For many years, drones from North Korea have penetrated South Korean airspace and conducted surveillance on sensitive government and military facilities.
In 2014, a drone believed to be from the North was found in the Seoul area and believed to have flown over the so-called Blue House, or the president's official residence. Also, a North Korean drone was recovered earlier this year near the border after it had reportedly taken photographs more than 100 miles away of the U.S.-supplied THAAD missile defense system.