North Korea has yet again launched a ballistic missile off its east coast peninsula, South Korea's Joint Chiefs Of Staff (JCS) have said.

The JCS said that the missile, launched from South Hwanghae province on Wednesday, landed in Japan's economic exclusion zone, heightening tensions in the region.

The medium-range missile, which flew roughly 1,000km before landing into Japanese waters, was believed to be a Rodong-type missile.

"North Korea is openly showing its direct and obvious intention of provocation."

South Korean Defense Ministry official was quoted by CNN as saying: "North Korea, by firing of ballistic missile which can equip nuclear warhead, is openly showing its direct and obvious intention of provocation and ambition that it can target our country, including our ports and airports, as well as neighbour countries.

"North Korea, whose provocative acts are threatening the peace and stability of the Korean peninsula and the international community, will be faced with more powerful and thorough sanctions and pressure from the international community and our country."

The US Strategic Command believes that North Korea simultaneously launched two missiles, with one exploding immediately after launch and the second one landing into the sea.

North Korea is repeatedly conducting missile launches despite UN Security Council prohibition on the use of ballistic missile technology.

Earlier in July, North Korea test-fired three ballistic missiles that flew between 500km and 600km into the sea.