Holly Madison and Crystal HarrisHugh Hefner's ex-girlfriend Holly Madison slammed Hefner's ex-fiance Crystal Harris on Twitter after she saw found out that Harris was appearing at a pool party in Las Vegas on her canceled wedding day.

Harris attended a pool party at Wet Republic at the MGM Grand Hotel in Las Vegas on Saturday, the day of her now-cancelled wedding, and Madison was made aware of the event by Las Vegas gossip columnist Norm Clarke. "#HughHefner's 'Runaway Bride' #CrystalHarris to appear at Wet Republic at #MGM Grand for a girls' getaway. #vegas," Clarke tweeted.

Madison tweeted, "That's a new low!!!"

Even famed celebrity writer Robin Leach talked about the event and the significance of the day it was held at, "Paparazzi mob scene prediction : Runaway Playboy bride Crystal Harris in LV today instead of Mansion wedding ceremony! Quick booking!!!"

Madison replied to Leach's tweet by and added her own thoughts, "That's disgusting and whoever booked her is tacky!"