The presidential office in Seoul said the USA and South Korean militaries will proceed with their ongoing war games even more thoroughly in response to the launch. The launches occurred in the midst of the United States and South Korea's annual military exercises.
A spokesman for US Pacific Command, using times at its Hawaii-based headquarters, said: "The first and third missiles at 11.49am and 12.19pm failed in flight".
Japan's military said the projectiles did not appear to be objects that could threaten Japan's safety. "The second missile launch at 12:07pm appears to have blown up nearly immediately", Pacific Command said, using times at its Hawaii-based headquarters.
Pacific Command spokesman Cmdr. David Benham said in a statement.
Kim says North Korea's large-sized artillery rockets blur the boundaries between artillery systems and ballistic missiles because they create their own thrust and are guided during delivery. "We place confidence in our US Department of Defense capabilities and continue open communications with our federal and military partners".
Yoshihide Suga told reporters the missiles early Saturday did not fall into Japan's territorial waters or the coastal 200-mile economic zone.
Tens of thousands of South Korean and USA troops are taking part in the "Ulchi Freedom Guardian" joint military drills, a largely computer-simulated exercise that runs for two weeks in the South.
North Korea this week said the exercises were evidence that the United States planned to invade North Korea. But this time, CNN's Will Ripley is the only western journalist there during this tense time.
There were eight Americans on board Ripley's flight to Pyongyang. USA officials say none of the missiles posed any threat to North America at any point.
Mr Tillerson said he was "pleased" to see Pyongyang had "demonstrated some level of restraint that we've not seen in the past".
Solid fuel missiles are faster and easier to deploy, and harder to catch before they launch because there's a lot less to be done in terms of launch preparation.
"They could be ballistic missiles but they could be rockets".
Throughout the year, North Korea has conducted a series of ballistic missile tests.
The country has fired 18 missiles during 12 tests since February, further perfecting its technology with each launch.
The North's move was immediately reported to President Moon Jae-in.