North Korea has fired an "unidentified projectile", believed to be a ballistic missile, towards Japan, South Korean officials have said.

The object was launched from the Wonsan region on North Korea's east coast and aimed eastwards, the South Korean Joint Chiefs of Staff said in a statement.

President Moon Jae-in of South Korea has called an emergency meeting of the National Security Council to assess the launch.

The projectile is believed to be a Scud-type missile that travelled around 280 miles before landing in the Sea of Japan, South Korean military sources said.

A Japanese government minister confirmed the missile appeared to have landed in Japan's waters but said no damage had been caused.

"This ballistic missile launch by North Korea is highly problematic from the perspective of the safety of shipping and air traffic and is a clear violation of United Nations Security Council resolutions," said Yoshihide Suga, the chief cabinet secretary.

"Japan absolutely cannot tolerate North Korea's repeated provocative actions. We have strongly protested to North Korea and condemn its actions in the strongest terms."

In pictures: North Korea military drill Show all 8 1 /8 In pictures: North Korea military drill In pictures: North Korea military drill North Korea's leader Kim Jong Un watches a military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) KCNA/Handout via REUTERS In pictures: North Korea military drill A military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) is seen in this handout photo by North Korea's Korean Central News Agency (KCNA) KCNA/Handout via REUTERS In pictures: North Korea military drill A military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) is seen in this handout photo by North Korea's Korean Central News Agency (KCNA) KCNA/Handout via REUTERS In pictures: North Korea military drill A military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) KCNA/Handout via REUTERS In pictures: North Korea military drill A military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) KCNA/Handout via REUTERS In pictures: North Korea military drill This image made from video of still images broadcast in a news bulletin by North Korea's KRT, shows what was said to be a 'Combined Fire Demonstration' held to celebrate the 85th anniversary of the North Korean army, in Wonsan, North Korea. KRT via AP Video In pictures: North Korea military drill This image made from video of still images broadcast in a news bulletin by North Korea's KRT, shows what was said to be a 'Combined Fire Demonstration' held to celebrate the 85th anniversary of the North Korean army, in Wonsan, North Korea. KRT via AP Video In pictures: North Korea military drill This image made from video of still images broadcast in a news bulletin by North Korea's KRT, shows what was said to be a 'Combined Fire Demonstration' held to celebrate the 85th anniversary of the North Korean army, in Wonsan, North Korea. KRT via AP Video

The White House said Donald Trump had been briefed about the latest launch. The US Pacific Command said it had detected and tracked the short-range missile for six minutes, determining that it did not pose a threat to the US.

North Korea has test-fired a number of missiles in recent weeks, with the latest launch taking place on May 21, when a rocket landed in the sea off its east coast.

It recently ordered largescale production of a medium-range ballistic missile capable of reaching Japan and major US military bases.

The Pukguksong-2 rocket was approved by North Korean dictator Kim Jong-un.

“Saying with pride that the missile's rate of hits is very accurate and Pukguksong-2 is a successful strategic weapon, he approved the deployment of this weapon system for action,” the KCNA state news agency reported.