North Korea has positioned what is believed to be a long-range ballistic missile on a launch pad, a U.S. counterproliferation official said.
Pyongyang has said it would launch a satellite between April 4-8 that regional powers believe will actually be a test of its longest-range missile, the Taepodong-2.
Following are some facts about the missile.
The Taepodong-2 is a two- or three-stage missile with a designed range of 6,700 km (4,160 miles), which means it could hit Alaska. It has a possible warhead payload of 650 kg to 1,000 kg (1,450 to 2,205 lb) in its short range configuration. One study has said that, with a reduced payload, the missile could travel 10,000 km (6,200 miles), which would theoretically put the western U.S. mainland within range. Research reports say a two-stage Taepodong-2 is about 35 meters long and has a diameter of 2.2 meters.
North Korea says the rocket launch, expected from April 4 to 8, is intended to put a satellite into space under its peaceful scientific program. The U.S. and South Korean governments believe it is a disguised test launch of the Taepodong-2, part of the North's nuclear, chemical and biological weapons program. Missiles and their technology are also a lucrative source of income for the impoverished state, and research reports say Iran has shown interest in buying the Taepodong-2.
The Taepodong-2 has suffered from problems brought on by merging a Chinese design with the North's own medium-range Rodong ballistic missiles. This has led to structural flight problems that also decreased the missile's intended range.
The Taepodong-2 has never flown successfully. Its only test launch in 2006 failed when the missile fizzled and destructed about 40 seconds into flight because of what is generally believed to be a structural failure in its airframe, propulsion system or fuel tank.
South Korea, with financial and technological resources far superior to the impoverished North, is bound under the Missile Technology Control Regime to developing ballistic missiles with ranges of 300 km (185 miles) or less.
The backbone of its missile arsenal is the 300-km ballistic missile named Hyun-mu. It has successfully developed a cruise missile that is known to strike a target at 1,000 km (625 miles).
(Source: U.S. Congressional Research Service, South Korea's Defense Ministry, GlobalSecurity.org, Reuters)
(Reporting by Jack Kim; Editing by Paul Tait)