WASHINGTON (AP) — The man accused of opening fire at the White House Correspondents' Association dinner railed against Trump administration policies and referred to himself as a "Friendly Federal Assassin" in writings sent to family members minutes before the shooting that authorities increasingly believe was politically motivated, according to a law enforcement official familiar with the investigation.

The writings, sent shortly before shots were fired at the Washington Hilton, made repeated references to President Donald Trump without naming him directly and alluded to grievances over a range of administration actions and recent events, including U.S. strikes on drug smuggling boats in the eastern Pacific, the official said.

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The official was not authorized to discuss the ongoing investigation and spoke on condition of anonymity.

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.

Authorities also uncovered what the official described as numerous anti-Trump social media posts linked to the suspect, Cole Tomas Allen, a 31-year-old California man accused of trying to breach a security checkpoint at the dinner while armed with multiple weapons.

Suspect's brother reached out to Connecticut police

Allen's brother contacted police in New London, Connecticut, after receiving the writings, according to the official. In a statement, the New London Police Department said it was contacted at 10:49 p.m., about two hours after the shooting, by an individual who wanted to share information related to it. The police department said it then immediately notified federal law enforcement.

Federal agents have also interviewed Allen's sister in Maryland, who told investigators her brother had legally purchased several weapons from a California gun store and stored them at their parents' home in Torrance without their knowledge, according to the official.

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She described her brother as prone to making radical statements, the official said.

Allen legally bought a .38-caliber semiautomatic pistol in October 2023 and a 12-gauge shotgun two years later, according to the official and another law enforcement official who also spoke on condition of anonymity because they were not authorized to discuss the ongoing investigation.

Acting head of Justice Dept. says Trump officials were targets

Authorities are still trying to determine how specific Allen's alleged targets were. Officials have said investigators are examining whether his grievances centered on Trump and Vice President JD Vance personally or reflected a broader hostility toward the administration.

Allen is believed to have traveled by train from California to Chicago and then onto Washington, where he checked himself in as a guest days earlier at the hotel days earlier where the gala dinner was held with its typically tight security, said acting attorney general Todd Blanche. He is believed to have acted alone and is set to face criminal charges on Monday.

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Law enforcement officials who have interviewed Allen's relatives and examined the gunman's electronic devices and his writings preliminarily believe he intended to target administration members in attendance at the dinner. He attempted to charge into the cavernous ballroom at the Washington Hilton but was tackled to the ground in a violent scene that resulted in shots being fired, Trump being hurried off the stage unharmed and guests ducking for cover beneath their tables.

"It does appear that he did in fact set out to target folks who work in the administration, likely including the president," Blanche told NBC's "Meet the Press."

A profile of the shooting suspect emerges

Social media posts that appear to match the suspect show he is a highly educated tutor and amateur video game developer.

A May 2025 profile photo of Allen appears to match the appearance of the man in a photo of the alleged attacker being taken into custody that was posted Saturday night by Trump. The photo, posted to the social networking site LinkedIn, shows him in a cap and gown after graduating with a master's degree in computer science from California State University, Dominguez Hills.

Allen earned a bachelor's degree in 2017 in mechanical engineering from the California Institute of Technology in Pasadena. He listed his involvement there in a Christian student fellowship and a campus group that battled with Nerf guns.

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A local ABC station in Los Angeles included an interview with Allen during his senior year of college as part of a story about new technologies to help people as they age. He had developed a prototype for a new type of emergency brake for wheelchairs.

Allen contributed $25 to a Democratic Party political action committee in support of Kamala Harris for president in 2024, according to federal campaign finance records.

Chaotic scene unfolded minutes after gala began

The shooting at the security barricades happened minutes after the event got underway.

The Secret Service and other authorities swarmed the room as guests ducked under tables by the hundreds. Gasps echoed through the ballroom as guests realized something was happening. Hundreds of journalists immediately got on phones to call in information.

"Out of the way, sir!" someone yelled. Others yelled to duck. From one corner, a "God Bless America" chant began as the president was escorted offstage. Outside the hotel, members of the National Guard and other authorities flooded the area as helicopters circled overhead.

After an initial attempt to resume the event, it was scrapped for the night and will be rescheduled.

Trump was unusually conciliatory after what he saw as a third attempt on his life in less than two years. He suggested that his personal politics had made him a repeated target, but he also called for unity and bipartisan healing in an increasingly violent world.

"It's always shocking when something like this happens. Happened to me, a little bit. And that never changes," Trump told reporters in a hastily organized news conference at the White House late Saturday.

More coverage from the shooting outside the White House Correspondents' Dinner

• Trump calls for unity and bipartisan healing after another violent incident
• Trump unharmed after security incident at White House Correspondents' Dinner
• WATCH: Trump holds news conference after shooting at White House Correspondents' Dinner
• WATCH: D.C. officials share updates on the White House Correspondents' Dinner shooting