President Obama will travel to Arizona on Wednesday to pay tribute to the victims of last weekend's shooting in Tucson that left six dead and 14 more wounded, a senior administration official said.

One victim, Rep. Gabrielle Giffords (D-AZ) remains in critical condition after sustaining a gunshot wound to the head. She was meeting with her constituents outside a local Safeway when she was attacked. 

Earlier Monday, the President and his wife, Michelle, led a moment of silence on the South Lawn of the White House. Obama also asked that flags be flown at half staff this week to honor the shooting victims.

"All of us are still grieving and in shock from the tragedy that took place," Obama said Monday. "Right now, the main thing we're doing is to offer out thoughts and prayers to those who've been impacted -- making sure that we're joining together and pulling together as a country."

Jared Loughner, 22, has been accused of the shooting and appeared in a Phoenix court Monday to face five federal counts connected to the incident.