A man was arrested after showing up at Ariana Grande's Hollywood Hills home in the middle of the night, then flashing a knife when security tried to get him to leave.
23-year-old Aharon Brown's facing a felony brandishing charge for the incident, which our law enforcement sources tell us went down around 2 AM Friday on Ariana's property.
We're told Brown arrived and demanded to see the singer, and when security told him to beat it ... he refused and pulled a knife. LAPD was called to the scene and arrested him.
It's unclear if Ariana was home at the time, but if she was ... we're told she never came out during the altercation or Brown's arrest.
Our Ariana sources say she's filed for a temporary restraining order against Brown, and a judge has granted her one until an upcoming hearing.