The Joint Chiefs of Staff(JCS) say the two projectiles North Korea launched on Thursday are a new type of short-range ballistic missile and share similar traits to the Russian Iskander variant that Pyongyang test-fired in May.

In a briefing on Friday, the JCS said it made the assessment jointly with the U.S. after putting together various intelligence related to the incident.

The JCS said both missiles are estimated to have traveled 600 kilometers, correcting an earlier military assessment that the projectiles flew 430 kilometers and 690 kilometers, respectively.

The JCS said it is carrying out further analysis and seeking to clarify what similarities exist between Thursday's missiles and the projectiles launched back on May fourth and ninth.