Amanda Bynes reportedly had a set to with Paris Hilton at nightclub 10ak on Thursday night.
Bynes is believed to have arrived at the nightclub with a male friend, before the actress sat herself at a table that was already occupied by Hilton and friend Brandon Davis.
Hilton and Davis were not happy with the sudden presence of Bynes, and words are believed to have been exchanged by the pair.
A witness to the incident told the New York Post's Page Six Column: "Amanda tried to sit at Paris and Brandon's table, and they were not happy about it.
"There was a scene, and words exchanged, before they kicked her out of their area."
The witness went on to say that Bynes continued to act strange for the rest of the evening.
The source continued: "Amanda wasn't drinking, but she was acting really weird. She stood in the middle of the club with her friend, looking really awkward, and just seemed totally out of it."
Amanda - who was released from a psychiatric facility on October 30 - has reportedly been diagnosed with bipolar disorder and was recently recorded on tape threatening to kill her own parents, Rick and Lynn Bynes.
She said: "I don't want to shoot my father in the face, and that's why I said I want to like strip for him as a joke.
"I want to literally like lead him into a ditch and ... I have't decided how I'd want to murder him, because now I have like this war wound on my face, and I don't believe in murder. Nothing would give me greater pleasure than like, slitting his throat."
TMZ said Amanda's family members wanted the tapes released because they might act as "wake-up call for medical professionals to intervene and get her help".
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