SEOUL (Reuters) -- North Korea fired what appeared to be two short-range ballistic missiles into the ocean off its east coast on Sunday, military officials in South Korea and Japan said, the latest in an unprecedented flurry of launches this month.
Two "short-range projectiles" were launched from the coastal Wonsan area, and flew 230 kilometres (143 miles) at a maximum altitude of 30 kilometres (19 miles), South Korea's Joint Chiefs of Staff reported.
Japan's Ministry of Defense said they appeared to be ballistic missiles, and they did not land in Japanese territory or its exclusive economic zone.
They would be the eighth and ninth missiles launched in four rounds of tests this month as North Korean troops conduct ongoing military drills, usually personally overseen by leader Kim Jong Un.
That would be the most missiles ever fired in a single month by North Korea, according to a tally by Shea Cotton, senior researcher at the James Martin Center for Nonproliferation Studies.
"Coming this early in the year, the only time we've seen tests this frequently were in 2016 and 2017, both of which were huge years for North Korea's missile program," he said in a post on Twitter.
The last test launch was on March 21. Based on photographs released by North Korean state media at the time, analysts identified those weapons as KN-24 short-range ballistic missiles.
United Nations Security Council resolutions bar North Korea from testing ballistic missiles, and the country has been heavily sanctioned over its missile and nuclear weapons programmes.
This month's military drills have been conducted despite a border lockdown and quarantine measures imposed in North Korea in an effort to prevent an outbreak of the new coronavirus, or of the disease the virus causes known as COVID-19.
The politically and economically isolated country has not reported any confirmed cases, though some foreign experts have raised doubts over that.
March has been a typical time for North Korea to conduct military drills, including tests of its ballistic missiles.
For the previous two years, however, it had avoided such springtime launches amid denuclearisation talks with the United States.
Those talks have since stalled, and this year's string of tests and military drills appear aimed at underscoring North Korea's return to a more hard-line policy, said Ankit Panda, a senior fellow at the Washington-based Federation of American Scientists.
"There is an element of projecting a business-as-usual image amid the COVID-19 situation, but I think it's not overriding," he said. "These tests do allow Kim Jong Un to show that he's sticking to the hard-line policy he laid out in December 2019."