CHICAGO (CBS) — Hundreds of people jumped into the icy Lake Michigan today to help some neighbors in need.

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The air temperature at Oak Street Beach was 20 degrees and it was 19 degrees warmer in the water at the 12th Annual Polar Bear Plunge, hosted by the Lakeview Polar Bear Club.

Stacy Monahan is an organizer.

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“It is for charity. It it’s a little bit closer to home because we don’t do it for like a giant charitable organization, we select families that are local and help them out,” said Monahan.

This year it is a marathon runner who got hit by a car and the family of a sick child. Some do it though just to do it.

“Oh we got American flag speedos, all of us, yes we do, just celebrating America,” said one group.

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According to organizers, 550 people took part and raised $70,000.