Cole Tomas Allen, 31, has been charged on three counts after entering the Washington Hilton Hotel on Saturday evening (April 25) and opening fire.
Chaos descended upon the annual dinner, held for members of the press and the presidential administration, as shots rang out as the gunman ran past security, carrying a 12 gauge pump-action shotgun, three knives and other weapons.
Allen, a 'game designer and teacher' according to his Linkedin, has now been charged on three counts, while appearing in court in Washington DC today (April 27).
He has been charged with attempt to assassinate the President of the United States, using a firearm during a crime of violence, and the transportation of firearm in interstate commerce with intent to commit a felony.
The federal prosecutor, Jocelyn Ballantine, noted that Allen crossed multiple state lines in an attempt to assassinate President Trump.
While standing in front of the courtroom in the capital this afternoon, Allen did not enter a plea to the charges.
Chaos erupted at the annual dinner when numerous shots were fired minutes after the event got under way. (Andrew Harnik/Getty Images) The next hearing for the suspected shooter will be on Thursday (April 30), which will be a detention hearing.
This determine's whether the 31-year-old should continue to be detained up until his trial.
The man charged of opening fire at the annual dinner sent writings to family members minutes before the shooting referring to himself as a 'Friendly Federal Assassin', officials reported.
The messages, sent just minutes before shots were fired at the Washington Hilton, made repeated references to President Trump without naming him directly, and alluded to political anger over a range of administration actions and recent events, including US strikes on drug-smuggling boats.
Investigators are treating the writings, along with a trail of social media posts and interviews with family members, as some of the clearest evidence yet of the suspect’s mindset and possible motives.
The shooting happened just minutes after the event got under way, as guests are welcomed into and out of the hotel as usual throughout the high-profile event.
Numerous Secret Service agents swarmed the room as more than 2,000 guests ducked beneath their circular dining tables.
The president held a short press briefing at the White House following the attack. (Nathan Howard/Getty Images) Trump appeared calm during the brief press conference following the shooting, after a third attempt on his life in less than two years.
When speaking about why he believes these attacks seem to keep happening so frequently, the president responded that he was 'honored', noting that his personal politics had made him a repeated target.
He said: "I’ve studied assassinations and I must tell you, the most impactful people - the people that do the most... the people that make the biggest impact, those are the ones they go after.
"They don’t go after the ones that don’t do much because they like it that way. When you look at the people... whether it was an attempt or successful attempt, they’re very impactful people... They’re big names."