"These were short range. These aren't any particularly big, big missiles," Joint Chiefs of Staff Chairman Mark Milley said.

While the Pentagon was still analyzing its data, "I don't think it's particularly provocative or threatening to us," Milley said.

"It may be tied to some celebrations that are happening inside North Korea, as opposed to any deliberate provocation against us."

South Korea's Joint Chiefs said the North earlier Tuesday fired what were believed to be short-range cruise missiles from Munchon into the sea, one day before Seoul holds parliamentary elections.

The firing also came a day before the nuclear-armed North marks the 108th anniversary of the birth of founder Kim Il Sung, grandfather of the current leader Kim Jong Un.