<p>MERCURY, Nev. (AP) — Authorities shot and killed a man who entered a secured federal site north of Las Vegas where the government used to test nuclear bombs.</p>
<p>A spokesman for the National Nuclear Security Administration says the man failed to stop at the security gate on Monday at the Nevada National Security Site. Darwin Morgan says the man drove for about 8 miles before he parked, got out of his car and approached security officials.</p>
