North Korea conducted a missile launch over Japan early Tuesday morning, further ratcheting up tensions in the region.

The incident was announced by South Korean officials who say the missile was launched from Sunan, near North Korea's capital, Pyongyang. Japanese officials say the projectile flew over the northern Japanese island of Hokkaido and landed in the Pacific Ocean.

Pentagon spokesman Col. Rob Manning confirmed the news in a brief email. He said American officials are still assessing the launch and that North American Aerospace Defense Command "determined the missile launch did not pose a threat to North America."

Japanese Prime Minister Shinzo Abe told reporters that his government was "aware of the movement of the missile immediately after the launch and had everything in order to protect the lives of our people."

Abe also said:

"The reckless act of firing a missile over our nation is an unprecedented, grave and critical threat and it is an act that significantly diminishes the region's peace and security, and we have lodged a firm protest."We have also requested an emergency meeting of the U.N. Security Council. We will work closely with other countries to intensify pressure on North Korea."

The launch marks the second time in four days that North Korea has tested its missiles. Three short-range missiles were launched on Saturday.

The New York Times reports that this is the first time a North Korean missile was launched over Japan since 2009. Pyongyang had also launched projectiles over Japan in 1998. Both times North Korea said the projectiles were carrying satellites.

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