"The launch appears to have failed," said an official with South Korea's Defense Ministry.
US officials suggest the missile may have fallen into the Sea of Japan.
"The North launched an unidentified missile from areas near Wonsan at around 5:58 am," said the Korean Joint Chiefs of Staff, according to Yonhap.
Reports surfaced earlier on Tuesday that Pyongyang had deployed a projectile to its east coast, though it was unclear if it was intended for launch.
"We have detected signs that the North has depoyed what appears to be a Musudan missile," Yonhap said, citing a South Korean government source.
The DPRK has test fired a number of ballistic missiles in recent months. These have been condemned by the United Nations, with the US, South Korea, China, and Russia urging Pyongyang to tone down the tests. Harsh new sanctions were put in place in response to earlier tests.
Pyongyang has also claimed to have developed a miniaturized nuclear warhead that could, theoretically, be launched with an intercontinental missile.