WASHINGTON — President Barack Obama is mourning what he calls "yet another mass shooting" in the United States that took the life of what he says were American patriots.
Obama promised to make sure, quote, "whoever carried out this cowardly act is held responsible."
Authorities said at least 12 people were killed in a shooting rampage Monday at the Washington Navy Yard about 3 1/2 miles from the White House.
Obama said the victims were "courageous Americans" who knew about the risks of serving overseas, but wouldn't have expected such "unimaginable violence" at home.
The White House said the president has been receiving frequent briefings about the unfolding situation by senior aides. He also telephoned Navy Secretary Ray Mabus to express his condolences to families and colleagues of the victims.