A pair of US aircraft carriers and Japanese warships in a joint drill (Photo:Reuters)

A pair of US aircraft carriers and Japan's Maritime Self-Defense Force (MSDF) began a 3-day joint drill in the Sea of Japan on Thursday. The strike groups of the USS Carl Vinson and the USS Ronald Reagan joined Japanese destroyers Hyuga and Ashigara in waters off the Korean peninsula. Japan also sent 8 escort vessels to the drill. Japanese Air Self-Defense Force F-15s took part in simulated combat with US Navy F-18 fighters. The drill came just days after North Korea launched a ballistic missile which landed in Japan’s exclusive economic zone.