A train ride, selfie and more: What DOJ says happened before press gala shooting

The suspect in the White House Correspondents' Dinner shooting appears to have started planning the attack three weeks ago when he began to search online about the event, according to new details in a memorandum prosecutors filed Wednesday in federal court. The filing includes more information about suspect Cole Allen's alleged movements on Saturday night, his apparent state of mind during his cross-country train trip to Washington, D.C., and how he allegedly planned the attack. It also includes a photo prosecutors say Allen took of himself in front of a mirror in his hotel room just before the attack, showing multiple weapons. "The defendant's actions were premeditated, violent, and calculated to cause death," prosecutors wrote in the memorandum. "It was, at its core, an anti-democratic act of political violence." Allen has been charged with multiple counts including attempting to assassinate the president of the United States. Allen's lawyers have not responded to requests for comment from CBS News. The timeline laid out by prosecutors notes that on March 2, President Trump publicly announced that he would attend the White House Correspondents' Dinner in a post on his Truth Social account. It was the first time he'd agreed to attend as president . …