SEOUL, March 18 (Reuters) – North Korea fired at least one ballistic missile on Friday, which flew about 800 kilometres before hitting the sea off its east coast, South Korea's military said, as the isolated state stepped up its defiance of tough new UN and US sanctions.

South Korea's Yonhap news agency said the missile was likely a medium-range Rodong-missile. If confirmed, it would mark North Korea's first test of a medium range missile, capable of reaching Japan, since 2014.

A TV screen shows a file footage of the missile launch conducted by North Korea, at Seoul Railway Station in Seoul, South Korea. Credit:Ahn Young-joon

The launch comes amid heightened tension on the Korean peninsula after the North rejected UN Security Council sanctions imposed earlier in the month in response to a nuclear test conducted in January and the United States issued fresh sanctions this week.

The missile was launched from north of the capital, Pyongyang, flying across the peninsula and into the sea off the east coast early Friday morning, the South's Office of the Joint Chiefs of Staff said in a statement.