Roughly 27,000 runners participate in the Boston Marathon annually. This year, dozens from Central Florida were competing. FOX 35 spoke with several people who ran in the race, one of whom was just a half-mile from the finish line at the time of the explosions.
Heather Schulz, of Orlando, finished the race before the bombing happened and had returned to her hotel just a half a block from where one of the bombs were detonated.
"Actually, for the last hour-and-a-half, all we've heard is sirens," she said. "It was insane. There had to have been 20 ambulances passing by."
Jennifer Florida, of Deltona, said she crossed finish line minutes earlier and was several hundred yards from blast. She said she didn't think it was a big deal, until she heard the sirens and saw that people were panicked.
"I had finished, maybe 15 to 20 minutes, prior to the noises we heard. I was getting my bag from the buses and heard the first explosion and then heard a second explosion. It kind of sounded like transmitters blowing. We weren't really sure what had happened. Some had speculated it was Patriot's Day and they were doing some sort of reenactment," she said. "Then, people started to run and trample each other."
John Hughes, of Orlando, ran in the race as his wife Betsy cheered from the sidelines. The two are co-owners of the Track Shack.
"As far as I know, (Betsy) was near the finish line," said Nathan Adams, manager of the Track Shack, "which is where the bomb went off."
Adams said Hughes finished 45 minutes before the explosion. Local runner Tara Gidis texted the couple as soon as she heard the news.
"I think they heard it from their hotel," said Gidis, "but I don't think they really saw anything, and then one of my other friends said it's absolute chaos up there."
David and Danielle Murphy, of Windermere, ran their personal bests on Monday morning, both finishing 30 minutes before the blasts.
"The first thought that went through our minds was, 'Wow! Had we not run the best race we ever ran that could have easily been us!'" David said.
Between 20 to 40 people ran as part of the running group organized by the Track Shack. Phone calls poured in to the store all afternoon from friends asking about the well being of fellow runners.
"Everyone we talked to is safe," said Adams.
While heartbreaking, new runners like Yumeko Motley said she is nervous but will still run her 5K this week.
"A little mixed emotion just because our safety is of the utmost concern," said Motley. "I think I'm confident that our law enforcement, knowing that the race is a few days away, will respond accordingly."
"You can't live your life afraid of everything," said Gidis. "You have to be able to live. This could happen anywhere, anytime, at any event. If you want to hole yourself in a house and never leave, that's your choice, but it won't stop me from running another marathon."
FOX 35's Kimberly Wiggins contributed to this report.