We originally thought this Craigslist ad threatening to poison area dogs was a cruel joke, but could there be a real-life Cruella behind it? The listing was put up earlier this month, warning, "I am hiding dog poison at dog runs," and has since been removed—but the NY Post reports that the city’s Parks Department is taking it seriously, and has put dog owners on notice in all five boroughs.

While there's been no evidence of poison at dog runs thus far, Parks says they have officers spot-checking them. They told the paper, “We are aware of the threat, and although it may well be a hoax, we are taking it seriously. We are working with the NYPD, Department Of Health/Animal Care and Control, and the ASPCA to investigate the matter.”

Do canine owners in all 5 boroughs really need to be concerned? One dog owner says, “The impression I got is it is a Park Slope issue," and the Parks Department seems to be focusing on the Dyker Beach and Owl’s Head Park dog runs.