Scott Pelley and Jeff Glor report from Boston, where Vice President Biden, city officials and survivors from last year's Boston Marathon bombing commemorate the anniversary with a moment of silence.
Scott Pelley iyo warbixin Jeff Glor ka Boston, halkaas oo madaxweyne ku xigeenka Joe Biden, saraakiisha magaalada iyo qaraxii Boston Marathon ee sannadkii hore ka badbaaday maamuusayay sanad guuradii la daqiiqad aamusnaan ah.