NBC Nightly News with Brian Williams
Security stepped up for the Boston Marathon
More: http://nbcnews.to/1i8pjFm

Security stepped up for the Boston Marathon

More: http://nbcnews.to/1i8pjFm

48-year-old runner becomes first with Down syndrome to finish NYC marathon Story: http://nbcnews.to/HwwjSm

48-year-old runner becomes first with Down syndrome to finish NYC marathon 

Story: http://nbcnews.to/HwwjSm

BREAKING: New York City Marathon canceled for Sunday, NBC New York reports