North Korea has deployed some 300 new multiple launch rocket systems (MLRS) along its front line with South Korea, which can hit Seoul and surrounding areas, military sources said Sunday.

Local sources, citing intelligence findings, said Pyongyang has placed the 122 millimeter rocket launchers north of the Demilitarized Zone (DMZ) that separates the two Koreas.

These weapons systems have an estimated range of some 40 kilometers that can place large areas in and around the capital city within striking distance.

"The North has been deploying the new rocket launchers with regimental units along the DMZ since 2014," said an official insider, who declined to be identified.

He said that there is a pressing need to counter such threats, adding that both Seoul and Washington have made joint threat assessments on these weapons systems.

The latest rockets while having the same diameter as those used to attack Yeonpyeong Island in November 2010, have twice the range.

There are two known variants of the MLRS, with one having 30 barrels per unit and the other having 40.

If the North fired off 30-barrel launchers all at once, it could send some 9,000 rockets into the South. With each projectile having a kill radius of about 30 meters, the barrage could result in considerable damage and loss of lives, if they land in populated areas.

The military said the rockets could place most of north Gyeonggi Province within their range, and theoretically hit northern parts of Seoul like the presidential Cheong Wa Dae and some areas of Incheon.

They will augment the country's 170 mm very long range self-propelled artillery pieces that can send shells 53 kilometers down range and the 240 mm MLRS that can fire projectiles as far as

64 kilometers. These large caliber rocket launcher systems will cover all of Seoul if placed near the inter-Korean border and reach as far south as Ansan and Seongnam.

“The new rockets will increase the number of MLRS and long-range artillery along the DMZ to over 600," another source said. He added if the North fields the even larger 300 mm rocket launcher systems with a range of around 200 km, it could target Gyeyong, where the headquarters of the South Korean military is located, as well as the U.S. military base in Pyeongtaek.

Military experts said that South Korea currently does not have weapons that can intercept such threats, and the only measure it can take is to carry out pre-emptive strikes, which entail serious risks of actually starting a conflict.

South Korea's military possesses the Chunmoo MLRS with a maximum range of some 80 km, as well as the Army Tactical Missile System (ATACMS) that can take out the North's rockets with its 300 km range. Its Air Force has a standoff land attack missile-expanded response system that can strike deep into North Korean territory.

The defense ministry, meanwhile, officially said it cannot confirm if the 122 mm MLRS have been deployed but stressed countermeasures to deal with such systems are included in the 2017-2021 midterm national defense plan. (Yonhap)