This is a developing story. Please check back for updates. (Last updated on Oct. 12 at 9:50 a.m. KST with information from Japan about a second launch.)

North Korea fired a suspected ballistic missile on Monday morning, according to Japanese and South Korean military authorities, the country’s fourth apparent missile test of the last month.

South Korea’s Joint Chiefs of Staff (JCS) released an alert after 9:20 a.m. KST that North Korea fired an unidentified projectile toward the East Sea (Sea of Japan).

Japan’s defense ministry released a similar alert at 9:24 a.m. KST, calling it a “suspected ballistic