CNN CNN International May 12, 2015 06:32:00
They say it hinges on rigorous safety standards. a south korean defense official estimates north korea could have a fully operational submarine armed with missiles within five years. over the weekend, pyongyang claimed it successfully test launched a ballistic missile from a sub, as brian todd reports, u.s. officials are examining images of that event very carefully. >> reporter: he's seen pointing at a missile launch which north korean officials say he ordered, beaming with pride with the submarine in the background. kim jong-un claims it successfully test fired a missile from a sub. one sa...