North Korea fired an “unidentified projectile” early Monday morning, South Korea’s Joint Chiefs of Staff said in a statement.
The projectile was fired from near Wonsan, Kangwon province.
The South Korean statement did not say where the projectile landed.
US officials are aware of the launch and “the president has been briefed,” a spokesman for the National Security Council said.
South Korean President Moon Jae-in was briefed and ordered a national security council meeting for 7:30 a.m. Monday local time (6.30 p.m. Sunday ET), the South Korean statement said.
North Korea has conducted a series of ballistic missile test firings recently.