North Korea fired multiple short-range ballistic missiles toward its eastern waters on Sunday, according to South Korean and U.S. officials.

The missiles were launched from the Sinpo area and flew about 140 kilometers, prompting coordinated monitoring and condemnation from South Korea, Japan, and the United States.

The tests come amid warnings from the International Atomic Energy Agency about rapid advances in North Korea nuclear program.

Officials said they are analyzing whether the launches involved submarine-based missiles, which would mark a significant escalation, Politico has reported.

The activity is part of a broader surge in North Korean weapons testing and heightened tensions over its expanding nuclear capabilities.