South Korea's military says North Korea has fired several ballistic missiles into the sea. The launch Monday happened hours after South Korean and U.S. troops kicked off their large annual combined drills,

North Korea has fired several ballistic missiles as South Korea and the United States initiated military drills. South Korea’s Joint Chiefs of Staff said on Monday that North Korea’s fifth launch event this year fired several missiles off the west coast into the sea.

North Korea has traditionally called for US-South Korea joint exercises to be called off, branding them as a prelude to invasion. The South Korean military has said the joint drills aim to strengthen the readiness of the alliance for threats such as North Korea.