Marathon Monday came to a screeching halt Monday afternoon after two bombs went off near the finish line on Boylston Avenue.
The bombs have killed three people, one of them an 8-year-old boy. More than 130 people are injured. Of those, at least 15 are in critical condition.
"I think it seems to me everybody is in shock. This doesn't happen in Boston," said Hugh Ryder, of Toronto, Canada.
As Marathon Monday comes to a close, police and S.W.A.T. teams filled the streets of a very unsettled downtown Boston.
"People want information. They want to know what's going on. I think people are concerned about loved ones, people who didn't get to finish the race," said Ron Marek, of Toronto, Canada.
Tens of thousands of runners came to the hub for the historic race, many still trying to make sense of exactly what happened this afternoon.
"All I saw basically was two big clouds of smoke that were consecutive, like I said, like two blocks away from where I was," said Anne Jensen, of Denver.
Chaos ensued in the moments following the explosions, and many scrambled to find loved ones along the route.
"My family was near the finish line waiting for me. And then you couldn't get a hold of them because there was no cell service," said Joseph Rotando, of New Jersey.
"I made it to a half mile from the finish line when they said the race was canceled. So my wife is actually running and I knew she was probably way behind me. So I was concerned about her, so I turned around, I probably shouldn't have, but I turned around and I made it two miles back looking for her before I realized they diverted everybody and there was no way I was going to find her," said Bill Buckley, of New Hampshire.
Shock consumes the minds of many who have looked forward to this tradition each year.
"I am devastated I mean this is supposed to be a happy day for people. People train and this is their dream to come here to Boston and run this race," added Jensen.
Copyright 2013 WSHM (Meredith Corporation). All rights reserved.