North Korea launched, Sunday, September 25, an unidentified ballistic missile in the East Sea, said the South Korean military, a few days after the arrival in the region of an American aircraft carrier with nuclear propulsion for exercises. "North Korea has launched an unidentified ballistic missile," South Korea's Joint Chiefs of Staff said, without giving further details. This launch, one of many carried out this year by Pyongyang, also comes following reports that North Korea may be preparing to launch an underwater ballistic missile.