This is breaking story. We will update this post as more details become available.
UPDATE 3:34PM EST: Lockdown at the White House has been lifted. Increased security presence remains.
UPDATE 3:09PM EST: Emergency personnel are on scene to treat multiple injuries, news sources are reporting.
UPDATE 3:07PM EST: The gunman has been taken into custody according to Fox News.
UPDATE 3:03PM EST: The Associated Press is reporting that one Capitol Police officer has been wounded by the gunman.
UPDATE 3:00PM EST: People outside the Capitol are being told to seek cover immediately.
UPDATE 2:56PM EST: The White House is locked down.
Reports of a shots fired at the US Capitol hill are sending DC into lockdown – the US Capitol has been locked down, with employees and visitors told to shelter in place.
Tweets from major news sources first announced the information, but were quickly confirmed by people on the ground.
BREAKING: Gunshots reported in U.S. Capitol visitors center, workers in Capitol told to "shelter in place": Senate sources
— Reuters Top News (@Reuters) March 28, 2016
Gunshots reported in the Capitol Visitors Center, we hear over the loudspeaker. Shelter in place, we're told.
— Emma Dumain (@Emma_Dumain) March 28, 2016
Local reporter Ellison Barber is saying that the shooter is down, but there has been no confirmation on this.
US Capitol Police source tells me shooting at visitor center – and "shooter is down." @wusa9
— Ellison Barber (@ellisonbarber) March 28, 2016