The writings, sent minutes before gunfire erupted on Saturday night at the Washington Hilton, contained repeated references to President Donald Trump — though not by name — and cited grievances over several government actions, including US operations targeting suspected drug-smuggling vessels in the eastern Pacific.

Investigators are examining the messages, alongside social media activity and interviews with relatives, as key evidence pointing to a possible political motive.

Authorities say the suspect, 31-year-old Cole Tomas Allen of California, had posted extensively online with anti-Trump views.

He is accused of attempting to breach a security checkpoint at the event while carrying multiple firearms and knives.

According to a law enforcement official, Allen’s brother alerted police in New London, Connecticut, after receiving the messages shortly before the shooting.

Local police said they were contacted at 10.49pm and quickly passed the information to federal authorities.

Investigators also learned from Allen’s sister that he had legally purchased several weapons from a California gun store and stored them at their parents’ home in Torrance without their knowledge.

She described him as someone prone to making extreme statements, the official said.

The writings themselves, spanning more than 1,000 words, shift in tone from casual to deeply unsettling.

Opening with a disarming “hello everybody!”, the message moves through apologies to family, colleagues and even strangers, before turning to a mix of personal grievances, political anger and farewell notes.

At points, the suspect invokes religious reasoning and responds to perceived critics.

He also mocked security arrangements at the Washington Hilton, expressing surprise that he was able to enter the venue armed without being detected.