North Korea tested a new underwater nuclear weapon earlier this week capable of spawning a "radioactive tsunami", Pyongyang's state media said on Friday.
The Joint Chiefs of Staff (JCS) said it detected the launches from Tongrim County in North Pyongyan Province between around 11:32 a.m. and 11:59 a.m., Yonhap news agency reported.
"If the US continuously persists in the grave military provocations, the DPRK will take into account more powerful follow-up measures," the spokesman said.
India's Permanent Representative Ruchira Kamboj joined US Permanent Representative Linda Thomas-Greenfield on Wednesday to issue a joint statement, along with nine other countries, to "strongly condemn North Korea's long-range ballistic missile launch which overflew Japan on October 4
The North launched one short-range ballistic missile (SRBM) on September 25, then two last Wednesday, another two the following day and two on Saturday.
The launches came just hours before South Korea was set to hold an event marking the Armed Forces Day with its key military assets on display.
"Work at the Punggye-ri nuclear test site paves the way for additional nuclear tests for the development of nuclear weapons."
The speaker of the US House of Representatives arrived in Taiwan on Tuesday night despite fierce protests from China, becoming the highest-level official to make a formal trip there in decades
North Korea has so far refused to accept millions of doses of Covid-19 vaccine proposed in the COVAX global distribution programme, as it had claimed to be coronavirus-free, with strict border controls in place over the past two years against the pandemic
The outbreak forced leader Kim Jong Un to wear a mask in public likely for the first time since the start of the pandemic, but the scale of transmissions inside North Korea wasn't immediately known. A failure to slow infections could have serious consequences because the country has a poor health care system and its 26 million people are believed to be mostly unvaccinated. Some experts say the North, by its rare admission of an outbreak, may be seeking outside aid.
During a military parade last month, the North showcased a set of SLBMs, including a "mini-SLBM" that it claimed to have successfully test-fired from a submarine in October last year.
Pyongyang conducted nearly a dozen rounds of missile launches over the cited period, including seven rounds in January that marked the largest number of missile tests it has undertaken in a single month
Pakistan's former President Pervez Musharraf admitted that Khan had given North Korea centrifuges for enriching uranium for nuclear weapons.
The North lobbed what appears to be a medium-range ballistic missile (MRBM) into the East Sea on March in its ninth show of force this year alone, the South's military said.
On Saturday, South Korea's presidential National Security Council convened an emergency meeting and condemned the North's missile launch, calling for Pyongyang to halt acts that raise tensions on the Korean Peninsula.