Puka Nacua's Accuser Receiving Threats, Cops Investigating, Attorney Says

3/26 -- Puka Nacua's attorney, Levi McCathern is teeing off on Joseph Kar, the lawyer for the accuser.

“Kar is a clown. Tried to make a mountain out of a very small mole hill and got caught. He’s trying to make millions off an incident that would of been forgotten by everyone within 48 hours if it didn’t involve a star football player."

"He’s also dumb as a stump. He’s the one that put his clients name out there. It’s in his original filings. He made no attempt to keep her confidential.”

The woman accusing Puka Nacua of biting her and making an antisemitic comment has been on the receiving end of threatening messages after filing a lawsuit and TRO against NFL star ... this according to her attorney, who tells TMZ Sports it's gotten to the point where police are involved.

We spoke with Madison Atiabi's lawyer, Joseph M. Kar, on Thursday ... and he explained how her name going public in court docs has resulted in Puka's supporters going after her.

"Police are investigating," Kar told us, "There have been some unkind statements and threats. She is understandably upset."

Kar is also placing some of the blame on Nacua's legal counsel ... claiming attorney Levi McCathern is attempting to smear his client's name, and is escalating the situation.

"It's a calculated attempt to litigate the case in the press using false narratives and cheap lawyer gimmicks that violate his professional and ethical duties as an attorney," Kar said.

"He seems to be the only person advocating for and trying to justify his client's sexual violence and long-time erratic behavior."

Kar's client alleges gender violence, assault and battery, and negligence in the lawsuit stemming from the New Year's Eve incident ... claiming she "suffered physical injury, pain and suffering, medical expenses, emotional distress, and other damages, in an amount to be proven at trial."

She also stated that Nacua -- who is entering the last year of his rookie contract this season -- said "f*** all the Jews" earlier in the night at dinner.

As for Nacua's side, McCathern says he's preparing to file a defamation suit against the accuser, claiming that sober witnesses at the gathering contradict the accuser's story, describing the TRO and lawsuit as nothing but a cash grab.

FYI, we obtained a video showing the accuser dancing in a passed-out Nacua's face ... and our sources say it came after the biting incident the night of New Year's Eve.