North Korea’s top missile commander accused South Korea of making false claims about a recent hypersonic missile test, according to a short interview released Thursday, drawing a prompt rebuttal from Seoul.

DPRK Missile Administration General Director Jang Chang Ha said “It is hard to believe that [South Korea’s hypersonic glide vehicle (HGV)] underwent hypersonic flight” during its Oct. 8 test, the Korean Central News Agency (KCNA) reported, in state media’s first mention of the test.

Photos released by South Korea’s Presidential Blue House of the HGV flying vertically and striking the ocean surface “may serve as evidence proving