It was a razor thin margin of victory for the men at this year's Boston Marathon...just one second separating the winner, Kenya's Lawrence Cherono from Ethiopia's Lelisa Desisa.

Cherono crossed the line in 2:07:59; Desisa came in at 2:08.

On the women's side though, Ethiopia Worknesh Degefa, who holds her home country's national record, cemented an early lead and won with a time of 2:23:30.

Mayor Marty Walsh says security was tight, on this sixth anniversary of the deadly Boston marathon bombing.

(SOUNDBITE) (English) BOSTON MAYOR MARTY WALSH SAYING: "We're working together to ensure that this event is safe for everyone because we'll all be looking out for each other." And after a rainy start, the weather finally cooperated as well....the sun shining on one of the most excting finishes in Boston Marathon history.