LAS VEGAS (AP) - A federal magistrate declined to order a psychological evaluation for a teenager accused of proclaiming himself a militia leader, collecting guns and explosives and talking about staging a mass casualty attack in Las Vegas.

U.S. Magistrate Judge Peggy Leen said Thursday it was clear that 18-year-old Steven Matthew Fernandes understands court proceedings in his case.

The Las Vegas Review-Journal reports that Leen told prosecutors they didn't provide a legal basis for seeking the evaluation.

Fernandes pleaded not guilty firearms and explosives charges following his September arrest with a loaded shotgun in his car on his way to work at a local RadioShack.

Agents reported finding explosives, rifles, handguns and thousands of rounds of ammunition in the Las Vegas home where Fernandes lived with his mother and two sisters.

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