Rob Kardashian added: "She cheated on me with nearly 20 dudes while we were together, I wonder how many she will sleep with now..."
Rob's older sister and X Factor USA host Khloe Kardashian Odom has also got in on the action by tweeting: "Cheaters never prosper @RobKardashian ill be home today… Try and smile little brother,' to which Rob replied with: "I Love You."
All tweets have since been deleted and Rita Ora is yet to comment. Obscenities are trending all over the internet.
What do you think? Do you believe Rob's taking to twitter was the right way to vent his frustrations?