Launch follows joint military drills by South Korea, Japan and the US and visit by Kamala Harris

North Korea has fired two more ballistic missiles, South Korea’s military said, its fourth such launch this week as Seoul, Tokyo and Washington ramp up joint military drills.

The launch early on Saturday came after the navies of South Korea, the United States and Japan staged trilateral anti-submarine exercises on Friday for the first time in five years, and the US vice-president, Kamala Harris, made a visit to the region this week.