The gunman who opened fire at the White House Correspondents' Association dinner took a cross-country train to the nation's capital before he checked into a room at the hotel where he carried out an attack targeting President Donald Trump and top administration officials, U.S. Acting Attorney General Todd Blanche said on Sunday.

Blanche and other officials did not name the man taken into custody in connection with the shooting. A federal law enforcement official confirmed to USA TODAY that the suspect is 31-year-old Cole Tomas Allen of Torrance, California. Federal agents could be seen swarming a home tied to Allen in Torrance after the April 25 shooting.

In an appearance on NBC News' "Meet the Press," Blanche said the suspect arrived in Washington, DC, via train from Los Angeles with a stop in Chicago. He added that the attacker is believed to have been a guest at the Washington Hilton, where the glamorous annual event took place.

Authorities say the suspect, armed with multiple guns and knives, charged past a security checkpoint before shots were fired. Trump, the first lady and top administration officials were whisked away by Secret Service agents as thousands of guests in tuxedos and gowns dropped to the floor. One agent was shot by the attacker, but was protected by a bulletproof vest. No one else was injured.