A man who was arrested at a Donald Trump rally in Las Vegas on Saturday after trying to grab a police officer's gun intended to "shoot and kill" the Republican presidential nominee, according to court documents released on Monday.

Michael Steven Sandford told a Secret Service agent after his arrest that he had traveled to Las Vegas on Friday from California and then gone to a Las Vegas shooting range on Saturday to learn how to shoot a gun. A complaint filed in U.S. District Court in Las Vegas also shows that Sandford told the agent that he expected to be killed by law enforcement in the act.

Sandford had a U.K. driver's license on him when he was arrested.

Attendees to Trump rallies have to undergo screening by the U.S. Secret Service, including a magnetometer to detect any possible weapons. Sandford was charged with attempting to commit an act of violence on restricted grounds.

Trump first requested Secret Service protection in October and was granted it in November.

The most visible threat to Trump so far during this campaign came in March. Agents had to surround the candidate during an appearance in Dayton, Ohio, when a man rushed the stage.

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