Federal authorities responded to the CIA headquarters in Virginia on Wednesday after a man brandished what appeared to be a handgun outside the building in an ongoing incident, sources told ABC News.

At one point, the man pointed a gun at his head, according to the sources.

Local police and security personnel were negotiating, the sources said.

A CIA spokesperson said there is an "ongoing incident that law enforcement is currently responding to outside" the CIA headquarters, located in Fairfax County.

"Additional details will be made available as appropriate," the spokesperson said.

The incident prompted a large police response, including from the FBI.

"Members of the FBI Washington Field Office's National Capital Response Squad and other FBI resources have been deployed to assist our law enforcement partners in response to an incident outside CIA Headquarters," the FBI Washington Field Office said in a statement.

This is a developing story. Please check back for updates.