PYONGYANG, North Korea, Dhu-AlQa'dah 23, 1437, August 26, 2016, SPA -- North Korea marked its "Military First" holiday on Thursday with mass dancing, outdoor concerts and boasts of a successful, and potentially game-changing, submarine-launched ballistic missile test it hopes will serve as a warning to Washington and Seoul to stop holding joint military exercises Pyongyang sees as a dress rehearsal for invasion, according to AP. Television news broadcasts and the front pages of morning newspapers Thursday showed images of the launch, conducted in the early hours the day before. The test, which brought immediate condemnation from the United States and North Korea's neighbors, sent a "Pukguksong" missile soaring from a submerged position off the North's port city of Sinpo. It flew an estimated 500 kilometers (310 miles) toward the seas around Japan, the longest distance North Korea has yet achieved in a submarine launch. Launching long-range ballistic missiles from submarines is stealthier than land launching. Having that capability could significantly strengthen North Korea's ability to conduct strikes on U.S. positions in South Korea, and possibly on U.S. bases in Japan as well. The North has attempted two such launches before, but neither was seen as successful by outside experts. --SPA 02:06 LOCAL TIME 23:06 GMT www.spa.gov.sa/w