Medium- and long-range missiles shown in Pyongyang, North Korea, in recent months are fakes and incapable of flying, according to U.S. government officials and independent analysts, reports Robert Windrem and M.L. Flynn of NBC News.

In addition, the man in charge of developing the missiles for the Far East state has disappeared.

"My opinion is that it's a big hoax," Markus Schiller, an aerospace engineer in Munich and former RAND Corp. military analyst told NBC about the rockets that have been displayed in North Korea since April.

U.S. government experts who reviewed images from the most recent parade of missiles agreed with Schiller. On the condition of anoymity, they told NBC, "Our assessment is that what we are looking at is most likely simulators used for training purposes.”

However, the experts did not reveal the methods they used to come to their conclusion.

Editor's Note: The original version of this story posted on Aug. 15, 2013, failed to properly attribute all source materials, which violates our editorial policies. The story was revised on Oct. 8, 2013 to attribute original source material. The story was also shortened to fall within our editorial guidelines for aggregation.