North Korea on Tuesday conducted its first test in two years of a submarine-launched ballistic missile, just hours after special envoys on North Korea met in Washington to discuss how to deal with the isolated country's nuclear capabilities. The council expressed "Deep regret" that the North had launched a missile amid international efforts to continue dialogue. The South Korean military said that the missile was fired from Sinpo, a city on the east coast where North Korea has often conducted its missile tests. The North called Pukguksong-5 a "Strategic" S.L.B.M., indicating that it was designed to carry a nuclear [warhead.It](http://warhead.It) remained unclear whether the S.L.B.M.s that the North has launched in recent years were fired from an actual submarine or a platform under the water. North Korea possessed only one submarine built to launch a ballistic missile and that vessel had only one launch tube. North Korea conducted its last missile test on Sept. 30, when it test-launched a newly developed antiaircraft missile. The country has conducted eight missile tests this year, including missiles launched from trains rolled out of tunnels and what the North claimed was a hypersonic missile.