The launch comes days after North Korea tested a suspected ICBM in the Sea of Japan.
North Korea has fired a ballistic missile toward the sea off the east coast of the Korean peninsula, the Yonhap news agency reported, citing South Korea’s Joint Chiefs of Staff (JCS).
The JSC didn’t immediately give details about Sunday’s launch.
The Japanese Coast Guard also said what was fired by North Korea could be a ballistic missile.
The launch comes after North Korea fired a suspected intercontinental ballistic missile (ICBM) into the sea between the Korean peninsula and Japan on Thursday, hours before South Korea’s president flew to Tokyo for a summit on ways to counter their nuclear-armed neighbor. to go.
North Korean state media described the launch of the Hwasong 17 as a response to ongoing, “frantic” joint exercises by South Korea and the United States.
Seoul and Washington have stepped up security cooperation after a year of record-breaking North Korean weapons tests and nuclear threats.
Pyongyang regards all such exercises as rehearsals for an invasion.
Last year, North Korea declared itself an “irreversible” nuclear power, and leader Kim Jong Un recently called for an “exponential” increase in weapons production, including tactical nuclear weapons.