Immediate evacuations ordered at US Capitol, police say 'no threat'

US House Speaker Nancy Pelosi said that Congress will investigate what went wrong in Wednesday's security scare, which turned out to be a military aircraft dropping parachutists into a baseball game.

 THE US Capitol building is blanketed with snow, in Washington, January 4. (photo credit: TOM BRENNER/REUTERS)
THE US Capitol building is blanketed with snow, in Washington, January 4.
(photo credit: TOM BRENNER/REUTERS)

A US Capitol Police alert was issued Wednesday evening causing moments of panic before officials responded that there was "no threat," in what turned out to be a military aircraft dropping parachutists into a Washington Nationals baseball game. 

“The USCP is tracking an aircraft that poses a probable threat to the Capitol Complex," US media reported that the alert said. 

 Security fencing is seen near the US Capitol ahead of rally in support of the Jan. 6 defendants in Washington (credit: REUTERS/MICHAEL WEEKES) Security fencing is seen near the US Capitol ahead of rally in support of the Jan. 6 defendants in Washington (credit: REUTERS/MICHAEL WEEKES)

An aircraft was seen flying low circles above the US Capitol building shortly before the report came out, a CNN correspondent confirmed. "Single engine aircraft. Parachutists into Nats Park. Not coordinated appropriately," CNN's Mike Valerio tweeted

US Capitol Police immediately tweeted that "there is no threat at the Capitol." 

"The Capitol was evacuated out of an abundance of caution this evening. There is no threat at the Capitol. More details to come," the police said in a statement. Buildings are being prepared for re-entry, it said, adding that a final update will be provided by the police later on Wednesday. 

US House Speaker Nancy Pelosi said on Wednesday night that Congress will look at results of after-action review that determines what went wrong in the security scare. She called the security alarm an "outrageous and frightening mistake" by the Federal Aviation Administration (FAA) for failing to notify the Capitol Police of the pre-planned parachute demonstration.

Reuters contributed to this report.