The United States and South Korea say North Korea appears to have failed in an attempt to launch a missile on April 15, likely to mark the birthday of its founding president.
A Pentagon spokesman said U.S. Strategic Command detected and tracked what it believes was a failed missile launch by Pyongyang.
That assessment echoes an April 15 statement by South Korea's joint chiefs of staff, which said the North "appears to have attempted a missile test near its east coast early Friday morning, but it appears to have failed."
South Korean media reported a day earlier that Pyongyang was preparing a midrange ballistic missile test as part of celebrations for the birthday of the North's founder, Kim Il Sung.
The Pentagon spokesman said U.S. Strategic Command systems detected the launch at around 5 a.m. local time on April 15 in North Korea.
The missile did not pose a threat to North America, the spokesman added.
A Strategic Command spokesman told Reuters that he had no details about the type of missile used in the launch. "We'll probably let North Korea characterize it themselves," he was quoted as saying.
South Korea's Yonhap news agency reported that it appeared to be a Musudan intermediate-range ballistic missile with a range of more than 3,000 kilometers.
China's official Xinhua news agency said the missile launch, despite its failure, was the latest example of saber-rattling by Pyongyang.
In recent weeks, North Korean media have carried repeated threats of preemptive nuclear strikes against both South Korea and the U.S. mainland.
The reported failed launch on April 15 follows Pyongyang's fourth nuclear test in January and a long-range rocket launch weeks later, which led to fresh UN sanctions.
A U.S. State Department official said Washington is monitoring the situation closely.
"We call again on North Korea to refrain from actions and rhetoric that further raise tensions in the region and focus instead on taking concrete steps toward fulfilling its international commitments and obligations," the official told Reuters.