A ballistic missile launched by North Korea flew 30 minutes and landed in the Sea of Japan, Japanese Chief Cabinet Secretary Yoshihide Suga said on Sunday.
South Korea's military said separately the missile had flown about 700 kilometres (430 miles).
Japanese Chief Cabinet Secretary Yoshihide Suga said on Sunday that North Korea's firing of a ballistic missile was a violation of U.N. resolutions and that Japan strongly protested the action.
Prime Minister Shinzo Abe repeated the protest in comments to reporters.
South Korea's military said earlier that North Korean had fired an unidentified projectile from a region near its west coast.
North Korea fired on Sunday an unidentified projectile from a region near its west coast, South Korea's military said.
The nature of the projectile is not immediately clear, a South Korean military official said by telephone.
Yonhap news agency reported the projectile launched appeared to be a ballistic missile.
