North Korea launches more missiles as Kim sister warns Pacific could become ‘firing range’

North Korea fired two ballistic missiles off its east coast, South Korea’s military said on Monday, as the powerful sister of the North’s leader, Kim Jong-un, warned the isolated and nuclear-armed state could turn the Pacific into a “firing range”.

The launches come just two days after North Korea fired an intercontinental ballistic missile (ICBM) into the sea off Japan’s west coast, prompting joint air exercises by the United States and South Korea on Sunday.

North Korean leader Kim’s sister, Kim Yo-jong, warned against the increased presence of US strategic assets on the Korean peninsula after the US held joint air exercises with South Korea and separately with Japan on Sunday.

“We are carefully examining the influence it would exert on the security of our state,” she said in a statement. “The frequency of using the Pacific as our firing range depends upon the US forces’ action character.”

North Korea’s state media confirmed it fired two projectiles from a multiple rocket launcher, aiming at targets 395km (245 miles) and 337km (209 miles) away.

“The 600mm multiple rocket launcher mobilised in the firing … is a means of tactical nuclear weapon” capable of “paralysing” an enemy airfield, state news agency KCNA reported.

Japan’s Defence Ministry said the two ballistic missiles fired on Monday morning reached a maximum altitude of about 100km and 50km, travelling a distance of about 350-400km before falling outside Japan’s exclusive economic zone.

“North Korea’s series of actions, including its repeated ballistic missile launches, threaten the peace and security of Japan, the region, and the international community,” the defence ministry said. “Japan lodged a strong protest and forcefully condemned North Korea.”

In a statement, the ministry said it would continue to gather and analyse information in close cooperation with the United States.

There were no reports of damage to aircraft or vessels.

US Indo-Pacific Command said: “While we have assessed that this event does not pose an immediate threat to US personnel or territory, or to our allies, the missile launches highlight the destabilising impact of the DPRK’s unlawful WMD and ballistic missile programs. The US commitments to the defence of the Republic of Korea and Japan remain ironclad.”

UN secretary general Antonio Guterres condemned the North’s earlier launch of an intercontinental ballistic missile and called on Pyongyang to cease “provocative actions”, his spokesman said on Sunday.

“The secretary general strongly condemns the launch of yet another ballistic missile of intercontinental range by the Democratic People’s Republic of Korea,” spokesman Stephane Dujarric said. He added that Guterres reiterated a call for Pyongyang “to immediately desist from taking any further provocative actions”.

Kim Yo-jong also rejected experts’ assessment of North Korea’s missile capabilities after some pointed out that it took over nine hours for the “sudden” missile launch to take place following an order from leader Kim. She said South Korea didn’t even fly reconnaissance planes at the time of its launch.

“We have possessed satisfactory technology and capability and, now will focus on increasing the quantity of their force,” she said.

Monday’s missile launch is the North’s third major weapons test this year after Pyongyang threatened an “unprecedentedly persistent, strong” response as South Korea and the US geared up for their annual military exercises as part of efforts to fend off the growing nuclear and missile threat that the North poses.