A fire drill of ballistic rockets by Hwasong artillery units of the KPA Strategic Force. Photo: KCNA

Korea’s ballistic missile test on Saturday ended quickly with a mid-air explosion, leading many to claim the test was a failure. But South Korean government officials say the explosion was intentional, reports the Korea Times.

“It’s believed the explosion was a test to develop a nuclear weapon different from existing ones,” one official was quoted by cable news channel YTN as saying.

While mid and long-range missiles tend to stabilize at 20 to 30 kilometers above ground, the missile launched Saturday reached 71 kilometers before exploding. Military experts say the chances of that happening due to mechanical failure are “very low.”

Since the North Korean media first used the term “test of nuclear warhead” at the time of the country’s fifth underground nuclear test, the South Korean military has raised concerns that a sixth test could be an “unconventional” above ground nuclear test.