A North Korean missile "blew up almost immediately" on its test launch on Sunday, the U.S. Pacific Command said, hours before U.S. Vice President Mike Pence was due in the South for talks on the North's increasingly defiant arms program.
The failed launch from the east coast, ignoring admonitions from major ally China, came a day after the North held a military parade in its capital marking the birthday of its founding father, Kim Il-sung, who is the grandfather of current leader Kim Jong-un. During that parade, the country appeared to display new ballistic missiles.
Pence is due in Seoul at the start of a 10-day trip to Asia in what his aides said was a sign of the U.S. commitment to its ally in the face of rising tension over North Korea.
A U.S. nuclear-powered aircraft carrier strike group is also heading for the region.
President Donald Trump was briefed on the launch, White House sources told NBC News.
"The president and his military team are aware of North Korea's most recent unsuccessful missile launch. The president has no further comment," Secretary of Defense Jim Mattis said in a statement.
The North has warned of a nuclear strike against the United States if provoked. It has said it has developed and would launch a missile that can strike the mainland United States but officials and experts believe it is some time away from mastering the necessary technology.
"The North attempted to launch an unidentified missile from near the Sinpo region this morning but it is suspected to have failed," the South's Office of the Joint Chiefs of Staff said in a statement.
Pence had been briefed on the failed launch en route to Seoul and had been in touch with Trump, the White House aides said. A senior White House official told NBC there was no indication that any change would be made to Vice President Mike Pence's four country, 11-day travel schedule, which had his arrival in Seoul set for Sunday.
South Korea's Yonhap news agency cited an unnamed South Korean intelligence source as saying the missile appeared to have not flown far from its land-based launch site.
The North launched a ballistic missile from the same region earlier this month ahead of a summit between the leaders of the United States and China to discuss the North's arms program.
China has spoken out against its missile and nuclear tests and has supported U.N. sanctions. China on Friday again called for talks to defuse the crisis.
That missile flew about 60 km (40 miles) but what U.S. officials said appeared to be a liquid-fuelled, extended-range Scud missile only travelled a fraction of its range before spinning out of control.
A U.S. Navy attack on a Syrian airfield this month with Tomahawk missiles raised questions about Trump's plans for reclusive North Korea, which has conducted several missile and nuclear tests in defiance of U.N. sanctions, regularly threatening to destroy the United States.
"[North] Korea missile test fails. But give them credit for trying. Test was in direction of US strike force. Undeterred by US muscle-flexing," Ian Bremmer, the president of consulting firm Eurasia Group and a closely followed political scientist, said in a tweet.
Sinpo, where the launch took place, is the site of a North Korean submarine base and where the North has tested the submarine-launched ballistic missile (SLBM) it is developing.
"It appears today's launch was already scheduled for re-launching after the earlier test-firing" Kim Dong-yub, a military expert at Kyungnam University's Institute of Far Eastern Studies in Seoul.
"This launch can possibly be a test for a new type of missile or an upgrade," Kim added.
Tension had escalated sharply in the region amid concerns that the North may conduct a sixth nuclear test or a ballistic missile test launch around the April 15 anniversary it calls the "Day of the Sun."
Ahead of this year's celebration, experts had warned festivities could take on a nuclear element as Kim looked to assert power following Trump's tough stance on the pariah state.
"It is highly likely that North Korea would engage in some form of provocation, another missile launch or even a sixth nuclear test, on or around April 15," Shawlin Chaw, senior analyst at Control Risks, told CNBC ahead of the event.
"The DPRK (Democratic People's Republic of Korea) has stated it is ready for war in response to the U.S. show of force this week and will most likely use the politically sensitive date to retaliate and reinforce its legitimacy with its own people," Chaw said, referring to a recent move by the USS Carl Vinson.
North Korea had only demonstrated military action twice on the anniversary in recent years. In 2012, it launched a long-range rocket carrying a satellite and last year, it tested an intermediate-range missile that reportedly failed.
The White House has said Trump has put the North "on notice" while the possibility of U.S. military action against Pyongyang has gained traction following U.S. strikes against Syria on
Impoverished North Korea and the rich, democratic South are technically still at war because their 1950-53 conflict ended in a truce, not a peace treaty. The North regularly threatens to destroy the South and the South's main ally, the United States.
—The Associated Press, CNBC's Nyshka Chandran and NBC News contributed to this article.