Today North Korea fired four ballistic missiles into the sea off Japan’s northwest, angering South Korea and Japan, days after it promised retaliation over U.S.-South Korea military drills it sees as a preparation for war.

South Korea’s military said the missiles were unlikely to have been intercontinental ballistic missiles (ICBM), which can reach the United States. The missiles flew on average 1,000 km (620 miles) and reached a height of 260 km (160 miles).

Some of the missiles landed in waters as close as 300 km (190 miles) from Japan’s northwest coast, Japan’s Defence Minister Tomomi Inada said in Tokyo.

Japanese Prime Minister Shinzo Abe said “strong protests” had been lodged with nuclear-armed North Korea, which has carried out a series of nuclear and missile tests in defiance of U.N. resolutions.