A 21-year-old man identified as Nasire Best was shot and killed by United States Secret Service personnel after he allegedly opened fire at a security checkpoint outside the White House on Saturday evening. Authorities said Best began shooting near 17th Street Northwest, prompting officers to return fire. At least one bystander was seriously injured, while no Secret Service personnel were reported hurt.

The incident occurred while President Donald Trump was inside the White House engaged in diplomatic discussions related to Iran and a proposed peace framework involving several Middle Eastern nations. The gunfire triggered panic among journalists and staff, who were ordered to take cover as armed officers secured the complex. The White House was placed under lockdown for about 40 minutes before restrictions were lifted.

Investigators said Best had a history of troubling behavior and prior encounters with law enforcement. Court records indicated he had previously claimed he was 'Jesus Christ' and had been involuntarily committed for mental evaluation after separate incidents near the White House. He had also been ordered by a judge to stay away from the grounds after attempting to bypass security checkpoints.

The Federal Bureau of Investigation confirmed it had launched a joint investigation with the Secret Service. Authorities noted that although Best had made disturbing statements in the past, he had not previously been known to carry a weapon or engage in violent conduct before the shooting.