South Korea on Saturday denounced the Democratic People's Republic of Korea (DPRK)'s test-firing of a submarine-launched ballistic missile (SLBM), saying it was in violations of UN Security Council resolutions regardless of whether it was successful or not.

South Korean foreign ministry said in a statement that the government strongly denounces the DPRK's another provocation to test-fire a SLBM in opposition to the international community's repeated calls and UN Security Council resolutions.

The ministry said the country will never tolerate Pyongyang's repeated and intentional provocations, including the test-launch of its Musudan missile on June 22, vowing to continue pressures and sanctions on the DPRK, including the complete implementation of UN resolutions, in close cooperation with major countries.

The statement also said that South Korea will continue to strengthen a combined deterrence with the United States against the DPRK's nuclear and missile threats.

The statement came after the DPRK fired a suspected SLBM at about 11:30 a.m. (0230 GMT) in waters southeast of the DPRK's eastern port city of Sinpo in South Hamgyong province.

South Korea's Joint Chiefs of Staff (JCS) was quoted as saying that the missile was normally ejected from a 2,000-ton DPRK submarine and was successfully ignited. But, it was estimated to have exploded in mid-air at an altitude of about 10 km, flying just several kilometers.

It marked the DPRK's first test-launch of its SLBM since April 23 when a ballistic missile fired from a submarine flew some 30 km before exploding and fragmenting into two to three pieces.

The launch came a day after Seoul and Washington jointly announced their decision to deploy the THAAD in the US Forces Korea (USFK).

The deployment decision was harshly denounced by China and Russia as the THAAD is part of the US pivot to Asia strategy.