The CIA said its security personnel took a person into custody early Thursday after an engagement outside the intelligence agency's headquarters.
A CIA spokesperson confirmed security staff "engaged a person" outside the main gates, adding the individual was in custody.
The spokesperson declined to say whether gunfire struck the suspect or to disclose any other details.
NBC News reported earlier that the person was shot, citing a person with knowledge of the matter.
The incident occurred around 4:00 AM (0800 GMT), a Fairfax police spokesperson told ABC News.
The CIA closed the main gate at its Langley compound and directed employees to seek alternate routes.
The shooting incident came after two Israeli Embassy staffers were killed by a lone gunman in downtown Washington on Wednesday night. There was no indication the incidents were related.

At least 14 killed in explosion at weapons depot in Syria
US hits five Iranian oil tankers after attack on Navy ships
UK gives air traffic provider a week to probe outage that halted flights
Serbia's President Vucic dissolves parliament, calls snap elections
With large crowds attending, Norway lays King Harald to rest
Jordan intercepts 18 Iranian ballistic missiles
Air traffic control issue disrupts flights at major UK airports
At least 73 injured after Houthi rebels attack Saudi civilian and energy facilities
