SEOUL - The Democratic People's Republic of Korea (DPRK) fired two ballistic missiles into its eastern waters early Sunday, Yonhap news agency quoted the South Korean military as saying.

The DPRK launched what were believed to be short-range ballistic missiles from the northern part of the southern border city of Kaesong, first at around 1:20 am and then around 1:30 a m, on Sunday, with their range estimated at about 500 km, according to an official with the Joint Chiefs of Staff (JCS) in Seoul.

The official added that the South Korean military has upgraded its vigilance and kept utmost combat readiness in case of more possible launches.

It was the DPRK's 14th launch of missiles or artillery shells this year. The DPRK has launched more than 90 short- and medium- range missiles and shells since Feb. 21.

The DPRK had fired two short-range missiles, which were presumed to be Scud, from a site in Hwanghae Province in a northeasterly direction into its eastern waters early Wednesday.

Yonhap quoted a South Korean government source as saying that South Korea and the United States will raise the issue of Pyongyang's recent missile launches with the UN Security Council's DPRK Sanctions Committee.

The new launch happened three days ahead of a joint maritime exercise that will involve US aircraft carrier USS George Washington and South Korean battleships in southern and southwestern waters off the Korean Peninsula from July 16 to July 21.

After the six-day drill, South Korea, the United States and Japan will hold a joint naval exercise, called Search and Rescue Exercise or SAREX, from July 21 to July 22 in international waters south of South Korea's southern resort island of Jeju.

The exercise will mobilize the USS George Washington, three ships and an aircraft from the United States, two ships and an aircraft from South Korea, and a ship and an aircraft from Japan.