CHICAGO (CBS) — Even for good swimmers, the Chicago River is dangerous.

That’s the message from two Chicago Police Marine Unit officers shown in dramatic rescue video.

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A woman fell into the water at the Riverwalk in Streeterville earlier this month.

Her boyfriend jumped in to help, but police had to save them both.

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Officers said it might not look like it, but the water is hazardous.

“The male occupant, his knees and legs were cut up from trying to hold onto the buoy,” said Officer Richard Antonsen. “Hypothermia sets in real quick. It can cause heart attack just on entry.”

“It’s not like going to the beach where it’s nice, smooth and sandy,” said Officer Mike Belluomini. “You have all kinds of obstacles in the river.”

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The officers also said because of COVID, people might not be used to the Chicago Riverwalk or the lakefront, so be extra careful.

CBS 2 Chicago Staff