The launches, the third round of missile launches in a week, were fired off separately from North Korea's eastern coast early Friday, South Korea's Joint Chiefs of Staff told Yonhap.
North Korea has fired unidentified short-range projectiles, the South Korean news agency Yonhap reported on Friday, citing the country's military as a source.
The nuclear-armed North described an earlier missile launch as a warning to the South over planned joint military drills with the United States.
The projectiles were fired in the pre-dawn hours from Yonghung, South Hamgyong Province, into the East Sea, the JCS told Yonhap.
Trump says he is not worried about short-range missiles
US President Donald Trump said on Thursday that he was not worried about missiles being tested by North Korea, calling them very standard, short-range devices.
Trump was asked about the missile launches as he left the White House on a trip to Ohio.
Asked whether North Korean leader Kim Jong-un was testing him by carrying out a third missile test in recent days, Trump told reporters: "I think it's very much under control, very much under control."
Trump added the missile launches did not violate any promises Kim had made to him.
They were "short-range missiles," Trump said. "We never made an agreement on that. I have no problem. We'll see what happens. But these are short-range missiles.
EU countries at UN condemn the missile tests
European Union members of the UN Security Council condemned North Korea on Thursday over its recent spate of missiles tests that have fueled fears Pyongyang is developing more advanced weapons.
Britain, France and Germany urged North Korea to "take concrete steps towards its complete, verifiable and irreversible denuclearisation and to engage in meaningful negotiations with the US as agreed between President Trump and Kim Jong-un on 30 June."
UN Security Council resolutions ban Pyongyang from ballistic missile launches but Seoul said devices fired on Wednesday from the Wonsan area on North Korea's eastern shore were two short-range ballistic missiles that travelled around 250 kilometres (155 miles).
"Serious efforts by North Korea to re-engage diplomatically and make progress on denuclearisation are the best way to guarantee security and stability on the Korean Peninsula, as well as a brighter future for the people of North Korea," the European countries said in a joint statement.
Pyongyang and Washington are engaged in a long-running diplomatic process over the North's nuclear and missile programs that has seen three high-profile encounters between the ir leaders in the space of a year.
They agreed to resume talks during their impromptu June encounter in the Demilitarized Zone that divides the peninsula, but that working-level dialogue has yet to begin.
"International sanctions must remain in place and be fully enforced until North Korea’s nuclear and ballistic missile programmes are dismantled. It is vital that the Security Council shows unity in upholding its resolutions," said Britain, France and Germany.