Updated

Vice President Joe Biden, Speaker John Boehner and former Rep. Gabby Giffords were on hand to dedicate a room in the Capitol Visitor Center to a congressional staffer killed two years ago in the attack on Giffords that took six lives.

Gabriel "Gabe" Zimmerman was the only staffer ever slain in the line of duty and Boehner pointed out that the meeting room named in his honor was the first room in the Capitol complex to be dedicated to a staff member.

Biden, like other speakers, referred to Monday's bombings at the Boston Marathon in telling the room full of family and friends that it is at the most difficult times that people stand closest together.

Others at the event included Democratic leader Nancy Pelosi and Arizona Sen. Jeff Flake.