SEOUL — South Korean technicians scrutinizing the debris of the North Korean rocket launched earlier this month have found evidence suggesting the rocket’s military purposes and the North’s technological ties with Iran in its efforts to develop an intercontinental ballistic missile, South Korean officials said Sunday.
North Korea insists that its Unha-3 rocket, launched Dec. 12 to put an earth-observation satellite in orbit, was part of its peaceful space program.
Intelligence officials and rocket scientists affiliated with the South Korean Defense Ministry said Sunday that through the rocket launching, North Korea was testing a ballistic missile that could fly more than 6,200 miles, with a warhead of 1,100 to 1,300 pounds, putting the US West Coast in range.
They spoke to the news media after having analyzed the rocket’s flight data and the debris from its oxidizer tank, which they recovered in waters off South Korea two days after the launching.
Over the weekend, the South Korean Navy also salvaged the remnants of the rocket’s fuel tank and part of its engine.
The officials said that they had so far concluded that the rocket’s first-stage engine was made of four North Korean ‘‘Rodong’’ missile engines attached together, and that the North Koreans had used a Scud-type missile engine for the rocket’s second-stage booster.
“They efficiently developed a three-stage long-range missile by using their existing Rodong and Scud missile technology,’’ a senior military intelligence official said Sunday, speaking on the condition of anonymity.
For an oxidizer, North Korea used red fuming nitric acid, commonly used as rocket propellant in old Soviet-built Scud missiles, as well as in Iranian and North Korean missiles, the official said.