All I have right now is a couple of tweets from a South Carolina reporter covering their congressional delegation, but we'll add more as it becomes available.

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

Capitol Police says something is going on outside and we are supposed to stay in the Senate press gallery so there's that.

— Emma Dumain (@Emma_Dumain) March 28, 2016

This message sent to @uscapitol workers and media based there. (I'm on campaign trail) pic.twitter.com/Gpo1JJZY6d

— Kelly O'Donnell (@KellyO) March 28, 2016

More as it's available.

Update 1:

UPDATE: Capitol's Sergeant At Arms: "Shooter has been caught. One police office shot, but not seriously. Remain sheltered in place."

— Jennifer Bendery (@jbendery) March 28, 2016

Update 2:

From a teacher who is currently there with his students:

.@Karoli we are on lockdown. Sweep being done to make sure it was just one shooter. We're told it was just one shooter. Shooter is down

— Danny Woo (@dannywoo15) March 28, 2016

Update 3 3:16 Eastern

MSNBC reports injury was a Capitol officer shooting an armed suspect before the suspect shot. The injury to the intruder is not considered serious, and he is being treated at a local hospital, presumably before being charged with illegal firearms possession.

Update 4: 3:28 Eastern

MSNBC reporting all clear.