North Korea conducted its latest submarine-launched ballistic missile (SLBM) test from an inland reservoir as part of its attempts to defeat U.S.-ROK missile defense systems, but such weapons are “effective” only when fired from a submarine, South Korea’s military said Tuesday.

Seoul’s defense ministry also stated that DPRK state media reports on recent missile tests and military drills revealed little new about the country’s weapons systems in its first remarks on the array of photos and details that North Korea published Monday.