The vice chairman of the U.S. Joint Chiefs of Staff says North Korea has failed in all three of its attempts to test its long-distance intercontinental ballistic missiles, with the latest failure coming during Sunday’s rocket launch.

James Cartwright made the comments during a briefing on the U.S. defense budget Tuesday in response to an inquiry about whether the recent North Korean rocket launch implies that Pyongyang has achieved meaningful technological improvements to its missile programs.

He said that Pyongyang failed to "transition from one stage of boost to the next" in Sunday’s launch.

Cartwright said the U.S. is investigating whether the North’s rocket failed to release the second- and third-stage boosters from the rocket, which reports say fell into the Pacific.