South Korea says North Korea has fired three ballistic missiles off its east coast in a show of force timed to the G-20 economic summit in China.

North Korea regularly engages in missile and rocket tests, especially when the world's eyes are turned to Northeast Asia.

World leaders are gathering for the G-20 summit of advanced and emerging economies in the city of Hangzhou in eastern China, which is the North's only major ally.

On Monday on the sidelines of the summit, South Korean President Park Geun-hye criticized the North for what she called provocations that are hurting Seoul-Beijing ties.