According to South Korea's Joint Chiefs of Staff (JCS), the country is monitoring the situation after North Korea fired unidentified short-range projectiles twice off its east coast on Friday.
"We are monitoring the situation in case of additional launches and maintaining a readiness posture," Yonhap News Agency quoted the JCS as saying.
The third such launch in a week, the projectiles were fired at around 2:59 am and 3:23 am from North Korea's Yonghung and South Hamgyong provinces into the East Sea. The JCS added that the two projectiles flew around 220 kilometers at an altitude of 25 kilometers.
More analysis was required to ascertain the exact type of projectiles fired, said the South Korean Presidential office.
The latest launches come just 48 hours after two short-range ballistic missiles were fired by North Korea from an allegedly new multiple launch rocket system.
Furthermore, North Korea had also launched two short-range missiles last week, which bore similarities with Russia's Iskander missiles. The new type of ballistic missiles have been codenamed KN-23.
Pyongyang claimed to have sent a "solemn" warning to Seoul through last week's launches, over South Korea's planned military exercises with the US.