A court heard on Wednesday that Rita Ora threatened to "f*** up" and "kill" a burglar.
The 25-year-old singer was woken at 5am on November 28 by the screams of her sister Elena, after a thief burst into her bedroom at their Kensal Rise home in northwest London.
The terrified star called 999 and sobbed as she threatened the intruder, who Elena says stole a jewellery box.
A recording of the call was played in Harrow Crown Court at the trial of Charaf Elmoudden, 26, who denies the charge of burglary.
Rita tells the operative: "I need you to come now, there is a robber in my house. I've just locked myself in my room, my sister saw him in her room. Please send them round now".
She's then heard shouting: "Don't you f*****g come up these stairs. I will f*** you up - you...hear me? Oh my God, I don't have a knife, I know they're going to come upstairs. What do I do? What do I do? Oh my God...I'm scared to go downstairs."
She adds: "What do you want me to do now? I will kill him."
The pop star gave evidence behind a curtain and broke down in tears when the recording was played.
She told the court as she composed herself: "That phone call freaked me out a bit - give me a moment" and continued: "I went to sleep and was woken up by a scream. I was half asleep, then woke up and heard my sister running up the stairs. I opened the door ... she just ran up the stairs then she jumped on my bed and started screaming."
Elena - who picked Mr Elmoudden out in an identity parade - also gave evidence and said she was "overwhelmed with fear" when she saw the intruder.
She said: "I wouldn't forget that face ever... At one point he was an arm's length away which was really scary because it means he was looking at me directly while I was asleep."
The trial continues.