The South Korean military is strengthening its protective facilities on the country’s five northwestern border islands with corrugated steel plates a military official said Monday.

It has been bolstering its defense capabilities on the islands near the tense western sea border since the artillery attack on Yeonpyeong Island in November last year, killing two soldiers and two civilians.

Additional high-tech weapons systems, including multiple-launch rocket systems, have been deployed to some of the islands, which military officials and experts say are of vital strategic value for national security.

“We have been replacing the concrete structures of some 100 Marine shelters and protective facilities on Yeonpyeong Island and Bangnyeong Island with corrugated steel plates,” said the official on condition of anonymity.

“Corrugated steel plates do not create many fragments after an enemy artillery attack. Thus, they will help reduce casualties in the event of an attack. They are also easier to install than the concrete structures.”

It is the first time for the military to use corrugated steel plates to reinforce military bases in South Korea. The military had used steel plates to construct facilities in overseas bases.

The Ministry of National Defense confirmed that protective facilities were being shengthened but refused to discuss detail.

The areas surrounding the border islands have long been regarded as a powder keg of the Korean Peninsula as naval clashes have repeatedly taken place there. The corvette Cheonan also sank in the West Sea last March in a North Korean torpedo attack that killed 46 sailors.

By Song Sang-ho (sshluck@heraldcorp.com)