Harry Styles is apparently "livid" that internet bullies have been targeting Taylor Swift.
Last month it emerged the One Direction hunk and the country singer have rekindled their romance.
Jealous fans calling themselves Directioners took to Twitter to voice their anger, with some even threatening to kill 22-year-old Taylor.
"Harry is livid. He just wants to date who he wants without fans going into overdrive every time he's linked to someone," a friend of Harry's told British magazine Star.
"He knows he gets a lot of attention from girls, but he's fed up. He just wants to have a normal love life and feels bad for Taylor."
Messages left by outraged fans included harrowing threats and vulgar language.
One user posted under the name of American Psycho serial killer Patrick Bateman.
"You're a f**king ugly b***h. I want to stab you to death and play around with your blood (sic)," they fumed.
Another tweet by a different user simply read: "If u dating my harry, I kill u (sic)."
The two young stars met in March and enjoyed a brief romance before splitting and pursuing other relationships.
Taylor went on to date Conor Kennedy, while Harry started seeing model Emma Ostilly, but both couples eventually fizzled out.