The man shot and killed by Secret Service officers outside the White House this morning had previously tried to enter the presidential building's grounds, including twice last year.

Three sources identified the gunman as 21-year-old Nasire Best, who this morning (Australia time) approached a security checkpoint and opened fire on agents.

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"Shortly after 6pm Saturday (8am Sunday AEST) an individual in the area of 17th Street and Pennsylvania Avenue pulled a weapon from his bag and began firing," the Secret Service said in a preliminary statement posted online.

"Secret Service Police returned fire striking the suspect who was transported to an area hospital where he was pronounced deceased. During the shooting one bystander was also struck by gunfire.

"No injuries were sustained by officers. The president was in the White House during the incident, however no protectees or operations were impacted.

"This incident remains under investigation and additional information will be released as it becomes available."

It's unclear whether the bystander was shot by Best or by officers.

Investigators recovered a pistol they believe belongs to the suspect, an anonymous official previously said.

Officers had encountered Best multiple times near the White House last summer, according to a court affidavit, which says he was "known to the Secret Service" for "walking around the White House complex inquiring how to gain access at various entry points."

He was involuntarily committed on June 26, 2025, for "obstructing vehicle entry" to part of the White House complex, the court documents said.

On July 10, 2025, Best ignored warning signs and walked into a restricted area outside the White House, the affidavit said, where multiple officers confronted him. Best claimed to be Jesus and said "that he wanted to get arrested," the report said.

A judge issued an order demanding he stay away from the White House grounds.

While investigating the encounters last year, investigators discovered Best had made various statements on social media, including claiming he was "the real" Osama bin Laden, and at least one post indicating his desire to harm Trump, the source said.

But police had never encountered the suspect behaving violently or wielding a weapon before, according to a law enforcement source.

Trump was at the White House during the shooting but was unaffected, and has been briefed on the incident, according to a spokesperson.

The building was locked down for about 40 minutes but has since returned to normal.

Journalists reporting on US President Donald Trump's claim of a nearly finalised peace deal with Iran were rushed to the briefing room and told to shelter in place after the noises were heard.

"I was in the middle of taping on my iPhone for a social video from the White House North Lawn when we heard the shots," ABC US reporter Selina Wang posted on X.

"It sounded like dozens of gunshots. We were told to sprint to the press briefing room where we are holding now."

A Secret Service official told CNN that the agency was investigating reports of shots fired at the corner of 17th Street and Pennsylvania Avenue Northwest, which is just outside the White House complex.

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Secret Service agents carrying rifles could be seen moving through the North Lawn area following the incident and blocking the White House press briefing room.

The Secret Service said it was "aware of reports of shots fired near 17th Street and Pennsylvania Avenue NW" — one block from the White House — and was "working to corroborate the information with personnel on the ground".

In a social media post, FBI Director Kash Patel said officers were responding to shots fired and said he would "update the public as we're able."

The lockdown comes a month after the White House Correspondents' Dinner, where reporters and Trump administration officials ducked for cover as shots rang out.

The suspect in that shooting, Cole Tomas Allen, sprinted through a security checkpoint with a shotgun in hand, exchanging fire with Secret Service agents who chased behind him, according to security footage.

He has pleaded not guilty to attempting to assassinate Trump and to other charges.

– with CNN and Associated Press