It said medical personnel were "responding to the male victim", but that there were "no other reported injuries".
That tweet came about two hours after the Secret Service first released information that it was responding to reports of a self-inflicted shooting along the White House's north fence.
Police in Washington DC confirmed that an "adult male has been declared deceased".
The White House the official home of the USA president, has been placed on lock-down.
Authorities were withholding the man's name until relatives were notified.More news: Neymar Injury: PSG Star Reportedly Out Vs. Real Madrid In Champions League
The man approached the fence line, removed a concealed handgun and fired several rounds, none of which appear to have been aimed at the White House, a Secret Service spokesperson said.
JOURNALISTS hid in the briefing room of the White House yesterday after a man shot himself in the head outside the gates.
President Donald Trump was away at his Mar-a-Lago resort in Florida, and was scheduled to return Saturday afternoon. A report of "shots fired" near North Lawn, per a U.S. Secret Service agent.
"You can get pretty darn close to the White House with a weapon", Hosko said, describing how security is tight around the White House, but people are allowed to get relatively close to the perimeter.