SEOUL, South Korea -- A huge mushroom cloud that reportedly billowed up from North Korea was not caused by a nuclear explosion, South Korean and U.S. officials said Sunday, but they said the cause was ...

WASHINGTON (Reuters) - The Pentagon has abandoned plans for a massive test explosion in the Nevada desert, the first time a mushroom cloud would have been seen near Las Vegas since a nuclear test in ...

LAS VEGAS (AP) - A huge non-nuclear explosion expected to generate a mushroom cloud in the Nevada desert will meet state air quality regulations, officials said Wednesday. State regulators have raised ...