WASHINGTON - A federal judge Friday denied a government request for a more thorough psychiatric evaluation of a man charged with firing shots at the White House in what prosecutors say was an attempt to assassinate President Obama.

The mental state of Oscar Ramiro Ortega-Hernandez, who prosecutors say harbored conspiracy theories and fantasies of killing the president, has been a critical issue since his arrest last month. Obama and his wife, Michelle, were out of town at the time of the shooting.

A preliminary psychiatric screening already found the suspect competent to stand trial, but prosecutors sought additional testing out of extra caution and to conclusively resolve any concerns about his mental well-being before trial.

They said the initial 50-minute screening was incomplete because it did not take into account some of Ortega's more bizarre or outlandish behavior and statements. They sought an additional inpatient exam.

U.S. Magistrate Judge John Facciola, in rejecting the request, said there was no evidence currently that Ortega was incompetent to stand trial. But he said prosecutors could renew their bid for another evaluation if they believe that Ortega's mental health is deteriorating as the case moves forward.

Ortega, 21 at the time of his arrest, sat silently and expressionless next to his lawyer during Friday's hearing.

Federal prosecutors say Ortega bought a gun, scope kit, and more than 1,200 rounds of ammunition and, after months of shooting practice, drove east from Idaho in mid-October with the goal of killing the president.

The night of Nov. 11, prosecutors say, Ortega pulled up across from the White House and, from more than 700 yards away, fired several rounds from a semiautomatic assault rifle out his car window.

Authorities say he drove away, crashed his car, and then fled on foot. He was arrested five days later at a Pennsylvania hotel.

Days after the shooting, authorities located at least five bullet impact points on the south side of the White House.