WASHINGTON, D.C. — Federal prosecutors filed a memorandum in U.S. District Court on Wednesday detailing the alleged movements and planning of Cole Allen in connection with a shooting at the White House Correspondents' Dinner on April 25 in Washington, D.C. The filing alleges Allen began plotting the attack three weeks before the event by searching online about the dinner.

Allen has been charged with attempted assassination of the president of the United States, which carries a maximum sentence of life imprisonment. He is also charged with discharging a firearm during a crime of violence and transporting firearms across state lines intending to commit a felony.

According to the filing, President Trump announced on March 2 via his Truth Social account that he would attend the dinner. On April 6, Allen used his cellphone to search for the dinner online and visited the White House Correspondents' Association website page for the event. That same day, he booked a room at the Washington Hilton for April 24 to April 26.

On April 16, Allen accessed articles about the dinner, including information about its host, Weijia Jiang, and the event schedule and expected attendees, according to the filing. He purchased a one-way Amtrak ticket from Los Angeles to Washington, D.C., via Chicago, and on April 21 booked a rideshare from Torrance, California, to Los Angeles Union Station. Prosecutors said Allen kept a running note on his phone of his observations during the cross-country trip and used the ride to research the dinner and the president's plans, viewing an article titled "Trump's Plans for 'Mic-Drop' Media Confrontation Are Leaked: The president is planning a rage-fueled moment at the White House Correspondents' Association dinner." After changing trains in Chicago on April 23, he continued reading articles related to the event.

Allen arrived in Washington on April 24 at 1:10 p.m., took the Metro to the Washington Hilton, and checked in around 3:15 p.m., according to prosecutors. On April 25, he came and went from his hotel room multiple times and looked up the president's schedule using a civic tracker website at around 6:26 p.m.

At 8:03 p.m., Allen took a selfie in his hotel room mirror wearing a black dress shirt and a red tie tucked into his pants, displaying a small leather bag, a shoulder holster, a sheathed knife, pliers, and wire cutters, according to an enhanced version of the image annotated by the Department of Justice. Ten minutes later, he rechecked a presidential schedule webpage before leaving his room. At about 8:27 p.m., he accessed a video of Trump exiting his vehicle en route to the dinner.

At about 8:30 p.m., prescheduled emails from Allen containing a text file titled "Apology and Explanation" were sent to members of his family, the filing states. The message said Allen planned to target Trump administration officials prioritized from highest-ranking to lowest.

Allen then rushed the screening checkpoint on the terrace level of the Washington Hilton with a raised shotgun, according to prosecutors. A U.S. Secret Service officer observed him fire the shotgun in the direction of the stairs leading down to the ballroom. Surveillance video shows an officer in black clothing and a vest marked "Police" raising his firearm and aiming at Allen.

Prosecutors allege Allen was armed with a 12-gauge shotgun, a .38 caliber pistol, two knives, four daggers, and enough ammunition to take dozens of lives when he was apprehended by Secret Service officers feet away from the ballroom where his primary target was located along with other Cabinet members. "The defendant's actions were premeditated, violent, and calculated to cause death," the memorandum stated. "It was, at its core, an anti-democratic act of political violence."

Acting Attorney General Todd Blanche told reporters that the shell casing from Allen's shotgun remained inside the shotgun.