PYONGYANG - The Democratic People's Republic of Korea (DPRK) fired two short-range missiles into its eastern waters Monday when the Republic of Korea (ROK) and the United States kick off their joint annual war games.

A ROK Defense Ministry official was quoted as saying that the DPRK fired two missiles, estimated to be Scud ballistic missiles, from 6:32 a.m. to 6:41 a.m. local time from Nampo areas, South Pyongan Province.

Those missiles, launched from Nampo, the DPRK's western coast city located southwest of capital Pyongyang, flied about 490 km across its territory into eastern waters

The launch came when the ROK and the United States launched their joint annual military exercises "Key Resolve" and "Foal Eagle" despite strong opposition from the DPRK.

Meanwhile, an unnamed spokesman for the DPRK's General Staff of the Korean People's Army issued a statement warning of "toughest measures" to retaliate against military exercises.

The army of the DPRK "will never remain a passive onlooker" to the drills, the statement said.

The retaliatory measures will include "all the ground, sea, underwater, air and cyber striking means" and the country's armed forces "are fully ready" to strike their designated targets.

Pyongyang said the "Key Resolve" and "Foal Eagle" war games which will last till April 24 are "dangerous nuclear war drills for invading the DPRK as they are aimed at swiftly hurling and forward-deploying the US imperialist aggressor forces in contingency on the Korean Peninsula."