projectile. the third in recent days. cnn has learned one of those launches caused a brief scramble when early warning systems first suggested it could hit the united states. cnn's selina wang live in tokyo with more. celina, this seems really significant. >> reporter: well, laura, we just learned new details about the most recent launch, the third one in two weeks from the south korean military. they're saying north korea fired two projectiles into the waters off the east coast, presumably short-range ballistic missiles. now, this came just hours after north korea lashed out at the united states, warning of stronger reaction to u.s. sanctions. the u.s. on wednesday had imposed sanctions on north korean and russian individuals tied to north korea's missile program. that announcement from the u.s. came after on tuesday north korea claimed it had successfully fired a hypersonic missile. that is what experts say would be a game changer, but they doubt the claims that it was, in fact, that sophisticated. however, south korea's military did, in fact, say it was more