Houston's police chief says the homes of 400 of his officers were destroyed or damaged by Harvey, but they stayed on duty during the storm. One officer, Bert Ramon, helped to save more than 1,000 people, even though he was fighting stage 4 colon cancer.

When Ramon posed for a picture, he was sending a signal to his wife, Cindy, reports CBS News' David Begnaud

"That's me giving a thumbs up that I'm OK. Don't let everybody worry about me," Ramon said.

The 24-year police veteran became one of the heroes of Hurricane Harvey, helping rescue nearly 1,500 people. Many were children – all were desperate.

"This is one where we unloaded all the seniors from an assisted living facility center in Kingwood," Ramon recalled.

For four days, it was treacherous. One police boat capsized and Sergeant Steve Perez drowned in his patrol car.

Ramon, who worked both Tropical Storm Allison and Hurricane Rita, said Harvey was "like apocalypse -- it was just unreal."

And it was dangerous for Ramon, who has stage 4 cancer. It has spread from his colon to his liver and lungs.

"I just said he does know his platelet counts are low? So he can bump, bruise, bleed easily? She says I know but it's what he wants to do," said Diana Reed, Ramon's case manager. That's what Cindy's wife told Reed.

"There's no way I can tell him you can't go. He looks at me and say you crazy. He says 'I'm going.' 'I'm going in,'" Cindy said.

Ramon just finished his latest round of chemotherapy Sunday.

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