myFoxchicago.com ran this article earlier this year explaining the Red-X initiative in Chicago:

CHICAGO (FOX 32 News) –

Big red “X’s” have recently gone up on more than a thousand buildings across Chicago, prompting lots of questions.

Residents of the South Side Auburn Gresham neighborhood complained that no one has explained the meaning of the big red “X’s” and one result has been some very wacky rumors.

“Some people think, you know, it reminds them of Katrina, New Orleans after Katrina, and the amounts of deaths and properties,” says Carlos Nelson of the Greater Auburn Gresham Development Corp. “Other people have mentioned World War Two and the Nazis and how they labeled Jewish homeowners.”

“The first response that I heard, that everybody thought that all these “X’s” meant all these buildings were coming down,” says Rev. Michael Pfleger. “And there was a sense, ‘Well, there’s gonna be a ton of abandoned lots in the neighborhood! What does this mean? We’re seeing it all over our neighborhood.'”

FOX 32 News traced this “X”-estential mystery to deputy Chicago Fire Commander Rich Ford, who had a dozen of them in his trunk. He said they’re posted as a warning to firefighters and other first responders that the building is vacant and could collapse. They should not enter, unless they have specific evidence someone’s inside and in danger.

Borrowed from New York, the Red X program was a response to the deaths of two firefighters killed in 2011 when a vacant South Side building’s roof collapsed on them.

“Almost immediately, we started getting strange calls,” Ford adds.

The Chicago Fire Department’s Richard Ford said up to 1,800 dangerous buildings will be marked and so far, 1,222 have been. A few have been repaired and won’t be torn down.

Tags: Chicago Fire Commander Rich Ford, Red-X markings in Chicago, South Side Auburn Gresham neighborhood, the Red X program