WASHINGTON (Yonhap) -- The Pentagon on Tuesday dismissed a news report that U.S. commandos have infiltrated North Korea on intelligence-gathering missions.

"It was misreported that there are U.S. boots on the ground in North Korea," George Little, spokesman for the Department of Defense, told reporters.

There have been long-time rumors that the South and North Korean militaries send spies across the border.

The two sides remain technically at war, as the 1950-53 Korean War ended in a ceasefire, not a formal peace treaty. As a legacy, the U.S. has 28,500 troops in South Korea.

"My understanding is that the general's comments were contorted, distorted, misreported and that, you know, there is in no way any substance to the assertion," the Pentagon secretary said.

He added the U.S. and Washington work closely "on a regular basis, on a daily basis, to develop all the information we can to assess North Korean intentions and capabilities."

"That is a fundamental responsibility we have. That's very important, and we'll continue to do that," he added.

In Seoul, meanwhile, U.S. Forces Korea (USFK) denied The Diplomat's report.

"Though special reconnaissance is a core special operations force mission (SOF), at no time have SOF forces been sent to the North to conduct special reconnaissance," USFK spokesman Col. Jonathan Withington said in a statement.