This picture from North Korea's official news agency shows a rocket launch on February 7, 2016.
The United States has issued a stern warning over North Korea’s new ballistic missile test, saying it was prepared to "defend ourselves and our allies."
On Wednesday, North Korea fired a ballistic missile from its western region into the sea off its east coast in what is believed to be a show of force after South Korea had deployed an advanced US missile defense system.
"We are aware of reports that the DPRK (North Korea) fired ballistic missiles," said State Department spokeswoman Anna Richey-Allen shortly after the test.
"We remain prepared to work with our allies and partners around the world to respond to further DPRK provocations, as well as to defend ourselves and our allies from any attack or provocation."
According to South Korea's Office of the Joint Chiefs of Staff, the missile was launched from South Hwanghae province to the southwest of the capital, Pyongyang.
Japanese Defense Minister Gen Nakatani also said that the launch posed a “serious threat” as the missile flew towards the Sea of Japan.
Richey-Allen described Washington’s commitment to defending its allies like South Korea and Japan as "ironclad."
She said that the US planned to rally against the test at the United Nations.
"We intend to raise our concerns at the UN to bolster international resolve in holding the DPRK accountable for these provocative actions," the spokeswoman said.
The north tested three other ballistic missiles on July 19, saying the launches were part of a drill simulating preemptive strikes against South Korean ports and airfields used by the US military.
On June 22, North Korea launched two Musudan mid-range ballistic missiles which both traveled over the Sea of Japan, also known as the East Sea.
The North has been placed under the toughest UN sanctions in two decades. The country, however, has pledged not to relinquish its nuclear power unless the US ends its hostile policy and dissolves its military command in South Korea.