By Roseanne Tellez

DES PLAINES, Ill. (CBS) — What started as a fun-run in the snow nearly turned tragic in Des Plaines yesterday. But it turned out to be a lucky day for a little boy who slipped into the river.

CBS 2’s Roseanne Tellez met the hero cop who saved him.

The off-duty officer who saved the day works in Evanston, but lives in Des Plaines. And if weren’t for him that little boy probably wouldn’t have had a chance.

But this is one low-key hero.

“Thinking about it, yes, like I said I just reacted. Any police officer that I work with here or anywhere else would have done the same thing,” said Evanston Police Officer Sean O’Brien.

O’Brien first spotted the boy has he dashed through traffic outside his family’s apartment building near River Road in Des Plaines.

Luckily, he still had sight of him when he grabbed a large snowball, headed toward the river and did the unthinkable.

“I just saw him underwater and I just jumped in to get him,” said O’Brien. “I called for him to give me his hand and I saw his hand come out of the water.”

Then he plucked him from the water and put him in his car, where his girlfriend and his new puppy helped calm him down.

When asked if the boy told him where his parents were, O’Brien responded, “No he was shook up by the whole thing. After the police were there, my girlfriend and I handed it over to police let them do their job.”

But today, the Des Plaines Fire Chief Alan Wax gave all the credit to O’Brien.

“Very heroic. Certainly if he wasn’t here and didn’t take the action he did it that would have been quite a tragedy,” said Wax.

At 26, O’Brien has only been a cop five years but has already saved two lives now. He’s also credited with saving a fellow officer from a burning car.

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