President Barack Obama is mourning what he called "yet another mass shooting" in the United States that he says took the life of American patriots.
Monday's mass shooting took place only 2 and 1/2 miles away from the White House, the closest the president has ever been to such an incident.
"So we are confronting yet another mass shooting and today it happened on a military installation in our nation's capitol," he says. "It's a shooting that targeted our military and civilian personnel. These are men and women going to work doing their jobs protecting all of us."
The president also paid tribute to victims.
"They're patriots, and they know the dangers of serving abroad, but today they faced the unimaginable violence that they wouldn't have expected here at home," he says.
On Capitol Hill, Majority Leader Harry Reid appeared briefly on the floor, before recessing until Tuesday morning in light of the shooting.
In South Carolina, Vice President Joe Biden reacted to the rampage.
"We know a tragedy's occurred and we're thinking about all the people who are there and praying for the safety of all the military and police personnel trying to bring this under control as well," he said.
The Associated Press contributed to this story.