North Korea fired what appeared to be two cruise missiles into the sea off its east coast, Yonhap news reported.
South Korea’s military is assessing Tuesday’s launches to determine the nature of the projectiles, Yonhap added.
NK News also reported two cruise missiles had been fired, quoting a South Korean military official.
The country’s Joint Chiefs of Staff did not immediately have confirmation of the report.
Cruise missile launches are not banned under United Nations sanctions.
In recent weeks, North Korea has defied international condemnation and conducted four rounds of ballistic missile tests.
Last week, the Academy of Defence Science conducted a test of two tactical guided missiles from the country’s west that “precisely hit an island target” off the east coast.
North Korean media also reported that the country’s powerful policy-making body, presided over by leader Kim Jong Un, saying it would consider resuming “all temporarily suspended” nuclear and intercontinental ballistic missile (ICBM) tests amid an ongoing effort to boost the country’s military against a “hostile” United States.
In recent months, Pyongyang has stepped up its rhetoric against US President Joe Biden’s administration while it conducted a series of ballistic missile tests, including what it has described as a new hypersonic missile.
In a separate development, Yonhap news agency said South Korea had detected no signs of North Korea trying to restore underground tunnels at the Punggye-ri nuclear test site despite indications of maintenance work there.
In 2018, Pyongyang announced that Punggye-rin had been demolished as part of an expression of willingness to denuclearise.