The interactive map published by the Journal News, prompting more than 1,300 comments as of Tuesday, allows readers to zoom in on red dots that indicate which residents are licensed to own pistols or revolvers.
"So should we start wearing yellow Stars of David so the general public can be aware of who we are??" wrote one commenter.
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Some of those responding threatened to cancel their subscriptions or boycott the publication completely.
"I hope you lose readers now," wrote one.
The map came about in the wake of the massacre in Newtown, Connecticut, according to a statement from The Journal News.
"In the past week, conversation on our opinion pages and on our website, LoHud.com, has been keenly focused on gun control," the newspaper's editor and vice president, CynDee Royle, said in the statement.
The names and addresses of the two counties' permit-holding residents were obtained through the Freedom of Information Act. The website notes that the map does not indicate whether the residents own handguns, only that they are legally able to, and that the data do not pertain to rifles or shotguns -- which can be bought without a permit.
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Still, hundreds of residents were shocked to see their information posted without their being notified. Some said the map will prompt burglaries because thieves are now aware of where weapons are likely located.
"Now everyone knows where the legal guns are kept, a valuable piece of information for criminals," a commenter wrote. "Why don't you do something helpful, like trying to find out where the illegal guns are kept?"
The Journal News argued that residents have a right to access information regarding weapon holders in Westchester and Rockland communities.
"Our readers are understandably interested to know about guns in their neighborhoods," Royle said in her statement.
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