US President Donald Trump was escorted out of a news conference after Secret Service agents shot and wounded a man who claimed to be armed outside the White House.
The Secret Service said the incident happened one block from the compound, when an officer fired on the suspect who had run "aggressively" towards him.
An agent then walked on stage as Mr Trump was speaking and led him away.
The president returned minutes later to say the situation was under control.
The US Secret Service said the incident happened on Monday on the corner of 17th Street and Pennsylvania Ave - outside the White House perimeter.
It said a 51-year-old man, who has not been identified, approached the officer, told him he had weapons and assumed a "shooter's stance", whereupon the officer shot him in the torso.
The Secret Service did not say whether the man was armed. It added that "both the officer and the suspect were then taken to hospital", and that "at no time during this incident was the White House complex breached".
After Mr Trump and his staff left, doors to the briefing room were locked with the journalists inside.
When the president returned nine minutes later, he said: "Law enforcement shot someone, it seems to be the suspect."
He said he did not know if the person harboured any ill intentions towards him.
"It might not have had anything to do with me," the president said.
A journalist asked Mr Trump if he was rattled by the events. He replied: "Do I seem rattled?"
The president added: "It's unfortunate that this is the world, but the world's always been a dangerous place. It's not something that's unique."
The District of Columbia fire department said a man suffered serious or possibly critical injuries, according to the Associated Press.
The news agency also reported that authorities were looking into whether the individual has a background of mental illness.