MATTHEW PENNINGTON
Associated Press

WASHINGTON (AP) — Recent satellite images show two new North Korean frigates, the largest surface combat ships the nation’s navy has constructed in a quarter-century, a North Korea-watching website reported Thursday.

The website, 38 North, says the frigates are designed to carry one helicopter each and appear to be designed to counter South Korean submarines and protect fisheries. The vessels appear to be equipped with anti-submarine rocket launchers.

The vessels can be seen in commercial satellite images from December and January. One is berthed at a shipyard in the west coast port of Nampo, other at a shipyard at the northeastern port of Nanjin.

It is unclear whether the frigates are yet ready for service.

The website is associated with the U.S.-Korea Institute at Johns Hopkins School of Advanced International Studies. The analysis is by Joseph Bermudez, an expert in satellite imagery analysis and North Korea’s military.

Bermudez notes that North Korea has been able to construct the vessels and other naval combat ships over the past decade despite international economic sanctions and reported industrial and economic stagnation.

Bermudez writes it will still likely take several years to integrate the frigates’ capabilities into its fleet operations.

“North Korea’s deployment of new helicopter frigates may be an important wakeup call not only about the overall effectiveness of sanctions in constraining Pyongyang’s conventional military programs, but also the need to carefully and realistically reevaluate reports of its conventional military decline,” he said.

Bruce Bennett, a senior defense analyst at the RAND Corp., said that the two new frigates would be bigger and more capable than the rest of North Korea’s surface fleet, which is viewed by many in the region as weak. While North Korea has a large submarine force and many patrol craft, it has little in the way of higher-end surface ships like frigates and destroyers, he said.

“Adding these two ships will not cause North Korea to have a very strong navy. If involved in a big conflict, the U.S. and South Korean navies and air forces could pretty quickly sink these ships,” Bennett told The Associated Press.

The U.S. has nearly 30,000 troops in South Korea, a legacy of the 1950-53 Korean War that ended without a formal peace treaty.

Bennett said that by investing in the frigates, the North’s authoritarian regime may be seeking to consolidate the internal support among naval personnel.

Bermudez said the vessels might also be used to protect fisheries in view of increasing pressure from South Korean, Chinese, Japanese and Russian fishing fleets.

Much of the international focus on North Korea is on its development of weapons of mass destruction, including speculation it may be readying its fourth nuclear test. But with tensions between the two Koreas running high, many analysts say the greatest risk of conflict lies in the North provoking the South with a conventional attack.

In 2010, South Korea accused North Korea of using a submarine to torpedo the South Korean ship Cheonan, killing 46 sailors.

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