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Amanda Bynes tweeted earlier that the New York Police Department's claim that she threw a bong out of window was false (" I've never had a bong in my life!" she wrote), and now, she's accusing the police officer who arrested her of sexual harassment.

"He lied and said I threw a bong out the window when I opened the window for fresh air. Hilarious," she tweeted. "He slapped my vagina. Sexual harassment. Big deal. I then called the cops on him. He handcuffed me, which I resisted, quite unlike any of the reports stated."

As a result, NYPD spokesman Det. Brian Sessa tells ABC News that as protocol, the police are conducting an investigation.

A police source disputes Bynes' version of events.

"She was on the phone with 911 making the allegations before officers entered the apartment," the source tells ABC News. "An independent witness, the building manager was [there too]."

Bynes, 27, was arrested Thursday night and charged with reckless endangerment, tampering with physical evidence and criminal possession of marijuana. She was arraigned and released Friday morning. But before she was booked, the former child star tweeted that she was "sent to a mental hospital."

"Offensive. I kept asking for my lawyer but they wouldn't let me," she tweeted. "The cops were creepy. The cop sexually harassed me, they found no pot on me or bong outside my window. That's why the judge let me go."

"Don't believe any reports," she concluded.

ABC News' attempts to reach Bynes' public defender were unsuccessful.