The rocket North Korea launched this week appeared to be more powerful than one fired in 2012, with an increased range of 12,000 kilometres (7,500 miles) which puts most of the US within reach, a South Korean defence ministry official said Tuesday.
The three-stage rocket was confirmed to have put an object into orbit but it has not yet been verified whether the alleged satellite is functioning, he told journalists, speaking on condition of anonymity.
The rocket was similar to the Unha-3 launched in December 2012 but is believed to have a range of 12,000 kilometres (7,500 miles), 2,000 kilometres more than the older model.
There had been speculation the North might use a much larger rocket this time after having completed work on an extended 67-metre (220-foot) gantry tower capable of handling a launch vehicle twice the size of the 30-metre Unha-3.
North Korea, however, has not yet mastered key technology needed to turn the rocket into an inter-continental ballistic missile — a re-entry vehicle to protect the warhead from heat, the official said.
The rocket, carrying an Earth observation satellite, blasted off Sunday at around 9:00 am Pyongyang time (0030 GMT) and, according to North Korean state TV, achieved orbit 10 minutes later.
The launch, widely seen as a disguised long-range missile test, sparked international condemnations and resulted in an agreement at the UN Security Council to impose new sanctions against the increasingly defiant state.
The flight path of the latest rocket was also similar to the 2012 launch vehicle, whose first stage debris was recovered by South Korea off its western coast.
North Korea this time is believed to have had the first stage of Sunday`s rocket blow up into 270-odd pieces to cover up its technical footprint, the official said.
The North is already subject to numerous UN sanctions over previous rocket launches and three nuclear tests in 2006, 2009 and 2013.