SEOUL - North Korea attempted and failed to launch what experts believe was an intermediate range ballistic missile on Friday in defiance of UN sanctions and in an embarrassing setback for leader Kim Jong Un.
The failed launch, as the reclusive country celebrates the "Day of the Sun" on the birthday of Kim's grandfather, follows the North's fourth nuclear test in January and a long-range rocket launch in February, which led to new UN sanctions.
But the North has nevertheless pushed ahead with its missile program, supervised by Kim.
The US-based 38 North website, which specializes in North Korea, has said there has been activity at the country's nuclear site based on satellite imagery, and on Wednesday said the possibility of a fifth nuclear test "could not be ruled out."
Friday is the anniversary of North Korean founding president Kim Il Sung's birthday which is widely celebrated. In 2012, it was marked by a long-range rocket launch attempt which also failed.
The US Defense Department said in a statement the launch at 5:33 a.m. Korea time was detected and tracked by the US Strategic Command which also assessed it had failed.
"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," a US State Department official said.