The South Korean military has been augmenting its anti-submarine warfare capabilities amid growing concerns over Pyongyang's submarine-launched ballistic missiles(SLBMs).

The Navy said on Wednesday that it has mobilized four of the eight AW159 Lynx Wildcat choppers for the first time since it purchased them from British manufacturer AgustaWestland last year.

The Navy said it will mobilize the Wildcat helicopters, the two-thousand-500-ton frigate Gwangju, and other military forces in the south of Geoje Island off the southern coast for various marine operations this month.

Installed on warships, Wildcat choppers carry out operations against submarines and battleships as well as assume marine reconnaissance missions. AgustaWestland’s AW159 Lynx Wildcats can detect enemy submarines that have a maximum speed of 296 kilometers per hour.

The Navy said four other Wildcats will be mobilized for military operations in July. The Navy also plans to buy 12 more helicopters designed for marine operations with the budget of 900 billion won, or 774-point-five million U.S. dollars, between 2020 and 2022.

In addition to the anti-submarine helicopters, the Navy is also seeking to strengthen its own submarine forces. A total of nine one-thousand-800-ton submarines will be deployed within several years, including five that were already constructed.

The submarines can perform underwater missions for more than two weeks continuously and are equipped with ship-to-surface cruise missile Haeseong III that can fly up to a one-thousand kilometers distance.

The South Korean military is also proceeding with the Jangbogo III program aimed at developing three-thousand-ton submarines that will be deployed after 2020.

The Navy is also in the final phase of a project to replace one-thousand-500-ton frigates and one-thousand-ton patrol gunboats with Incheon-class, two-thousand-500-ton frigates. A total of six such new frigates will be deployed by April.

A two-thousand-800-ton, Daegu-class frigate will also be put into service by next year.

The measures are being carried out in response to the rapid progress the North is allegedly making in SLBM technology, which could pose an immediate threat to South Korea.

The North test-fired SLBMs in April, July and August last year. In August, it succeeded in expanding the maximum range of its SLBMs to 500 kilometers by employing a high-angle launch.