A military official says a weapons promotional brochure showing the same type of torpedo that sank the Cheonan naval ship bears the official name of North Korea.

A military official said Tuesday that the brochure was clearly made by the North Korean government as it included the phrase “certified by the Democratic People's Republic of Korea,” which is the official name of the North.

Last week, the joint military-civic probe team on the sinking of the Cheonan informed the 15-member U.N. Security Council about the brochure via a video that contained images of the brochure.

Defense Ministry spokesman Won Tae-jae confirmed that the brochure indeed used the North's official name, but added it would be difficult to make the brochure available for inspection by the public, as information about its acquisition could cause diplomatic problems.

The joint military-civic probe team first mentioned the existence of the brochure when it unveiled its findings late last month. At the time, the team disclosed that a drawing from a torpedo brochure was the same type that sank the Cheonan.