By Dorothy Tucker

CHICAGO (CBS) — One year ago, Mark Busiak was in Boston and on Tuesday, he stood outside Old St. Pat’s where bells marked the anniversary of the Boston tragedy.

“I was part of something that was very evil,” said Busiak.

Busiak was just two blocks from the finish line where the bomb exploded, killing three people and injuring 264.

“You just feel sorry for the families,” said Busiak.

To pay tribute to the families, Busiak will return to Boston. He’s among the hundreds from Chicago who have been training for months.

Busiak said he has no fear and that is no one showed up, “Evil would win…We’re going to show the world how strong America is.”

“There’s no fear, no fear what so ever… What if no one showed up. Evil would win. Evil is not going to win.”

Fortunate to be alive to return is how Dr. Jim Ostenga views this year’s marathon. He was trying to beat his Boston record of four hours, four minutes and forty seconds. If he had, he might not be here.

“I was a little slower and in retrospect I feel like there was some divine influence that kept me away from the finish line,” said Ostenga.

Like thousands of others, Ostenga never crossed the finish line. Posters, photos, even the bib he wore in last year’s marathon is a reminder he must return.

“I think there will be a great celebration after the last runner crosses the finish line next Monday. It was show the resilience in the human spirit,” said Ostenga.

Runners from the Chicago area will join some 36,000 marathoners from around the world on Monday. That’s about 9,000 more than last year.

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