North Korea fires 3 ballistic missiles, South Korea claims

North Korea fired three ballistic missiles early on Tuesday into the sea off its east coast that had a range of between 500 and 600 kilometres, South Korea's military said.

The missiles were launched towards east from an area in the North's western region called Hwangju from 5:45 a.m. local time to 6:40 a.m., the South's military said.

"The ballistic missiles flight went from 500 kilometres to 600 kilometres, which is a distance far enough to strike all of South Korea including Busan," the South's military said in a statement.

Busan is a South Korean port city in the south.

North Korea has test-fired a series of ballistic missiles in recent months, in defiance of United Nations Security Council resolutions, including intermediate-range missiles in June and a submarine-launched missile this month. North Korea's military had threatened to retaliate against the deployment of the THAAD system with a "physical response" once its location and time of installation were decided.

China has also sharply criticized the decision to base a THAAD battery in South Korea, saying the move will destabilize the security balance in the region.

North Korea conducted its fourth test of a nuclear device in January, and activity at its nuclear test site has increased recently, according to media reports in South Korea and Japan citing government officials, as well as a report by Washington-based North Korea monitoring project 38 North.

Following Pyongyang's January nuclear test and a February space rocket launch that was widely viewed as a missile test in disguise, the U.N. Security Council imposed tough new resolutions that further isolate North Korea.

In addition to the decision to base a THAAD system in South Korea, the United States recently angered North Korea by blacklisting its leader Kim Jong-un for human rights abuses.