North Korea this week test-fired two ballistic missiles, apparently in protest at three days of joint military exercises involving the US, Japan and South Korea. Tensions between the two Koreas have risen in recent weeks. But it is not only missiles that the North is launching. It has also sent thousands of rubbish-filled balloons over the border, in response to balloons carrying anti-North Korean propaganda sent by South Korean activists. Constantin Simon, our correspondent in the region, Justin McCurry and Aruna Popuri explains the proxy balloon war raging on the Korean peninsula.
