PYONGYANG/SEOUL - The Republic of Korea military on Tuesday conducted "a serious provocation", firing more than 10 warning shots at soldiers of the Democratic People's Republic of Korea, the official Korean Central News Agency (KCNA) reported Saturday.

The DPRK soldiers were working on a permanent barrier project near the southern border line at that time, the KCNA said, citing a senior military official in its report.

The provocation is a "serious prelude that would inevitably drive the situation in the southern border area where a huge number of forces are stationing in confrontation with each other to the uncontrollable phase and the DPRK army is keeping tabs on the present situation", said Ko Jong-chol, vice-chief of the General Staff of the Korean People's Army, in a press statement issued on Friday.

At present, the DPRK army is conducting a barrier project to permanently block the southern border with the ROK as part of the regular work to reinforce the border, according to the statement.

Completely separating the territory is "the undertaking to eliminate the factor of escalated tension in the militarily acute southern border area and secure the stable environment", which poses no threat to anyone, it said.

To prevent misunderstanding and accidental conflict, the DPRK army had already informed the US forces of the barrier project on June 25 and July 18, the statement added.

The US forces accepted this as a sincere measure for detente and confirmed that the project by the DPRK personnel is being conducted within the sovereign territory of the DPRK, it said.

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"If the act of restraining or obstructing the project unrelated to the military character persists, our army will regard it as (a) deliberate military provocation and take corresponding countermeasure(s)," Ko said in the statement.

In response, the ROK's Joint Chiefs of Staff (JCS) said on Saturday that some of the DPRK troops had crossed the military demarcation line (MDL) while working inside the demilitarized zone at about 3 pm local time (0600 GMT) on Tuesday.

The JCS said that the ROK's forces had fired warning shots and the DPRK soldiers moved north of the MDL later. The ROK's military is keeping a close eye on the moves of the DPRK forces, it said.

US-ROK joint drill

Meanwhile, the DPRK condemned an ongoing major joint military exercise between the US and the ROK, saying it is "extremely provocative" and calling the two countries "chief culprits" who undermine peace on the Korean Peninsula, the KCNA reported on Saturday.

In a Friday press statement carried by the KCNA, a spokesperson for the General Staff of the Korean People's Army said the Ulchi Freedom Shield exercise, being staged on land, at sea and in the air of the Republic of Korea (ROK), is "an extremely provocative and aggressive large-scale drill for an actual war clearly aimed at a sudden preemptive attack on the DPRK."

The spokesperson underscored in the statement the gravity and danger of the drill, saying it includes the application of a war scenario simulating a preemptive strike against the DPRK nuclear facilities as well as various kinds of military maneuvering and live firing exercises.

"The reckless war drill of the US and the ROK warmongers is seriously threatening the security environment of the DPRK and pushing the situation on the Korean peninsula and in the region to the extreme tension," said the spokesperson.

The statement also noted that some British warships participating in a joint maritime drill in the Pacific Ocean entered the ROK's Busan operational base and other forces of "UN Command" member states joined the military drill, turning it into a multinational military drill and redoubling the military threats it posed to the DPRK, according to the KCNA report.

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The military drill "leads to the destruction of balance of power in the region and the chief culprit of harassing peace on the Korean peninsula is none other than the US and the ROK", said the statement.

The DPRK army will further bolster its full readiness, and will respond to the military provocations of the hostile forces posing direct threats to the safety of the country with "proper and indiscriminate exercise of the right to self-defense", the statement added.