A detailed examination into the background of Nasire Best - the 21-year-old gunman eliminated by the US Secret Service on Saturday night after a shootout at a White House security checkpoint - has exposed a severe history of mental instability and repeated security breaches targeting the executive mansion, The Washington Post reported.

According to judicial records and testimonies from acquaintances, the suspect's life spiraled down a dark path following his graduation from Dundalk High School in Baltimore County, Maryland, where he had competed as a track athlete.

An anonymous school companion described Best as a historically apolitical individual who was consumed by internet gaming and running. However, his senior year in 2023 was severely disrupted by constant bullying and a physical altercation that triggered a suspension, barring him from senior festivities and halting his athletic season.

By May 2025, Best's behavior grew profoundly erratic, according to The Washington Post report. He systematically severed ties with his social circle and cut off communication with close peers after becoming enraged when they refused to validate his delusional assertions that he was Jesus Christ.

Despite his escalating psychological deterioration, his mother, Rhonda Melvin, expressed shock over the fatal encounter outside the White House, claiming she only learned of her son's death via social media platforms.

“I’m still in disbelief right now," Melvin said when reached by phone. She said that Best “was never violent, regardless of what people are posting."

Federal law enforcement authorities confirmed that Best was the armed assailant who initiated the firefight at 17th Street NW and Pennsylvania Avenue NW, positioned immediately adjacent to the Eisenhower Executive Office Building.

“A preliminary investigation indicates that as the individual approached, he removed a weapon from his bag and began firing at posted officers," Secret Service communications chief Anthony Guglielmi said in a statement. “Secret Service police officers returned fire, striking the suspect, who was transported to an area hospital, where he later died."

The agency noted that a civilian bystander was struck during the chaos, though investigators are still determining whether the round originated from the perpetrator's weapon or the defensive fire returned by law enforcement.

Saturday's fatal encounter occurs amid a heightened climate of security threats surrounding the American president. On April 25, authorities thwarted what they described as an attempted assassination against Trump at a Washington hotel hosting the annual White House Correspondents' Association Dinner.

Days later, on May 4, Secret Service personnel shot another armed suspect after he allegedly opened fire on law enforcement officers near the Washington Monument. A teenage bystander was wounded during that confrontation.