The military aircraft was detected in South Korean airspace at 19.30pm local time (9.30am).
Known as the C-146 “Wolfhounds”, they are often seen with low-profile paint schemes to keep their missions secret.
The crafts are deployed across the world to provide logistical support for ground troops.
It comes after the Pentagon drew up plans to send more Special Ops soldiers to the Korean Peninsula.
More than 1,000 American reserve soldiers are also getting ready to be moved overseas with the Winter Olympics set to kick off in South Korea.
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**South Korea air traffic**
— ADSB TweetBot (@ADSBTweetBot) February 2, 2018
LIVE: South Korea airspace at 0930 UTC #ADSBTweetBot pic.twitter.com/qkE9I9r3y6
Special Ops have been deployed to large global events before – like the 2014 World Cup in Brazil – but their numbers will supposedly be far greater this year.
The deployment could see the formation of a Korea strike force ready to cripple Kim’s dictatorship.
The US and its allies have already stepped up military drills in a bid to intimidate Kim.
In December, thousands of US troops and 230 airplanes descended on the peninsula after his latest missile test.