Japan's navy and air force began a three-day military exercise with two U.S. aircraft carriers in the Sea of Japan on Thursday adding pressure on North Korea to halt an accelerating ballistic missile programme.

Japan's Maritime Self Defence Force has sent two ships, including one of its four helicopter carriers, the Hyuga, to join the U.S carriers, the USS Ronald Reagan and USS Carl Vinson, and their escorts, Japan's military said in a release. 

Japanese Air Self Defence Force F-15s are taking part in simulated combat with U.S. Navy F-18 fighters at the same time, the military said.

Source: Timesofoman