A brief statement Thursday from Seoul’s Joint Chiefs of Staff gave no further details, such as what kind of projectile was launched and where it landed. In the past, such reports by South Korea about North Korean launches have turned out to be test launches of missiles and artillery pieces.

The reported launch came three days after North Korea said its troops performed artillery drills near its disputed sea boundary with South Korea.

U.S.-led diplomacy on ending the North Korean nuclear crisis has remained stalled for months.