North Korea launched around a dozen short-range ballistic missiles at about 5 p.m. KST on Thursday, according to the South Korean military.

The Japanese defense ministry first released an alert through the coast guard at 5:08 p.m. warning vessels to watch out for falling objects. Another alert 11 minutes later said a suspected missile appeared to have “already fallen,” suggesting it was not a long-range missile.

South Korea’s Joint Chiefs of Staff (JCS) in a message to news agencies said around 12 missiles flew about 186 miles (300 km) before splashing down in the Sea of Japan, or East Sea.