The singer went on Twitter to rant about Hilton, after she had been informed by one of her fans that he was being shown an apartment inside her New York building.
The tweet has since been deleted, but Gaga angrily directed it to Hilton, saying: "STAY AWAY FROM ME + MY FAMILY YOU ARE SICK TRYING TO RENT AN APARTMENT IN MY BUILDING TO STALK ME. LEAVE ME ALONE!!!"
She then posted the following tweet, which has also now been deleted: "DO I NEED TO BE SHOT IT IN THE HEAD FOR PEOPLE TO UNDERSTAND THAT HIM AND EVERYONE ELSE THAT HARASSES ME HAS GONE TOO FAR? IM A HUMAN BEING.(sic)"
However, Hilton is not going to lie down and take Gaga's abuse! He has hit back at the singer with a blog post, titled A Statement On LadyGaGa's Lies (sic), in which he denied stalking her and set the record straight.
Hilton wrote: "[On] Sunday, my realtor showed us a list of possible apartments to rent. I learned only after the fact that Lady GaGa lives in one of the buildings we looked at, and she was across the country in Los Angeles when I viewed that building."
"After a day of innocent house-hunting, I am devastated and my heart hurts that my former very good friend, a person I used to call my "wifey" and traveled the world with, is making very public and very untrue allegations about me on Twitter."
“While it is still too painful for me to go into detail about why I chose to no longer make her a part of my life, I will say that I am a critic and not a 'stalker'."
"Any allegation that I am stalking her, based on a day of house hunting with my baby boy and my mother, is utterly false, defamatory and now appears to be putting me and my family in danger…"
Hilton, who has a 6-month-old son Mario Armando Lavandeira III, has also claimed he is receiving death threats from the Born This Way hitmaker's fans.
Shortly before the feud erupted, Gaga slammed Hilton on Friday via Twitter, claiming he had previously mocked her hip injury and had poked fun at the fact that she had to use a wheelchair.
Gaga wrote, "Still have the text Perez sent me of me in a wheelchair w the words KARMA written across + Madonna pointing a gun at me. Day of my accident (sic)"
To add insult to injury, Hilton has decided to make a little comment on Gaga's comeback single "Applause", writing on his blog, "Despite her best efforts, #LadyGaGa's comeback song continues to drop on @iTunesMusic in America. It's currently #8!"
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