SEOUL/PYONGYANG, June 29 -- The Democratic People's Republic of Korea (DPRK) on Sunday fired two short-range ballistic missiles into waters off its east coast early Sunday morning, the South Korean military said.

The news came just three days after Seoul reported that the DPRK fired three short-range projectiles into waters off South Korea's eastern coast at a time when tensions were running high on the Korean Peninsula.

"(The DPRK) fired each one missile presumed to be Scuds from the vicinity of Wonsan, Gangwon Province, at about 4:50 a.m. and 4: 58 a.m. into the East Sea," South Korea's Joint Chiefs of Staff (JCS) said Sunday.

"Their range is about 500 kilometers," it added.

According to a JCS official, the DPRK fired the missiles without designating no-sail zones, which the South Korean military view as a clear provocation.

The missiles fell into international waters off South Korea's eastern coast, the official said.

On Friday, the DPRK announced that it had test-fired "newly developed cutting-edge ultra-precision tactical guided missiles," without specifying when the launch took place.

DPRK leader Kim Jong Un oversaw the test-fire at the central monitoring post, according to the official KCNA news agency, which lauded the new weapons as "another shining success" in the efforts to manufacture "high-precision, lighter, automatic and intelligent weapons and equipment."

The test-fire also helped the Korean People's Army (KPA) get "the master key" to producing world-class short-, medium- and long-range guided weapons and maximize their striking precision and power, the KCNA added.

Kim "expressed great satisfaction" with the results and expressed the belief that his country would "manufacture more ultra-precision tactical guided weapons capable of taking the decisive initiative in any operation and battle of modern warfare."

The KCNA added that the test came at a time when the United States, South Korea and other allied forces were becoming "extremely reckless in the moves to isolate and stifle the DPRK and unleash a war of aggression."

"The rockets were fired in succession from coastal areas near its eastern city of Wonsan at around 5 p.m. in a northeastern direction, and landed in international waters," South Korea's Yonhap news agency quoted the JCS as saying on Thursday.

A JCS official said the range appeared to be "some 190 km" and that they were looking into what types of rockets were used.

Also on Thursday, the DPRK accused the South Korean military of firing shells toward the waters of the DPRK from the waters around Yonphyong Island "without any prior notice."

Describing the incident as a "reckless provocation," the Command of the Southwestern Front of the KPA warned that the KPA was fully prepared to strike back.

Later that day, the U.S. State Department said the country was trying to determine whether the firings violated the UN Security Council resolutions which ban Pyongyang from any ballistic missile activity in case such technology could be used to develop nuclear missiles.

"We're monitoring the situation and we're still evaluating the available information to identify the exact type of projectile that may have been launched," Marie Harf, deputy spokesperson of the State Department, told a press briefing.

"Obviously we wouldn't agree with any launch, but in terms of the technicality it depends on what they were," Harf said.

The two Koreas are still technically in a state of war as the 1950-53 Korean War ended with an armistice, not a peace treaty.

Animosity has been running high on the Korean Peninsula after the two sides exchanged artillery shells on the disputed western sea border on May 22, about two months after trading hundreds of artillery shells in late March.