>> reporter: president obama and the first lady here to pay tribute yet again to soldiers who so bravely marched in to battle only to lose their lives here at home. fewer than five years after a shooting here that left 13 people dead, the president again visiting the nation's largest army base as consoler-in-chief to the grieving families, to the wounded, and to a military community mourning once again. >> we are here on behalf of the american people to honor your loved ones and offer whatever comfort we can. >> reporter: just as he did in 2009, president obama met privately with some of the victims' families and the wounded. we learned of the 16 people hurt in the shooting here, four remain hospitalized. marcy gonzalez, abc news, ft. hood. >> thank you. there is word this morning that russia withheld vital intelligence on one of the boston marathon bombers. russian officials did tell the fbi that tamerlan tsarnaev was following radical islam.