The teen daughter of former "Law & Order" DA Dianne Wiest (search) has been busted with her girlfriends for beating up a boy and stealing his iPod, officials said Monday.

Emily Wiest (search), 17, and two other teenage girls were arrested Friday afternoon for allegedly roughing up a male classmate from the Beekman School in Manhattan and stealing his digital music player, court papers say.

Asked for comment, her actress mom said through the door of her Manhattan apartment, "I don't know what you're talking about," and declined to say anything else.

A courthouse source said the Academy Award-winner was acting — and had actually spent all day at Manhattan Criminal Court on Saturday awaiting her daughter's arraignment. The teenager was eventually released without bail.

A law-enforcement source said Emily Wiest, Lara Zieden, 18, and Leah Rucinski, 15, had gotten into an argument with the 16-year-old boy inside the East 50th Street school early Friday — and plotted to finish the fight that afternoon.

That's when the three jumped the teen, whose name was being withheld, during a recess about a block away from the school, court papers say. All three "punched and kicked" him "about the body," their criminal complaints say.

The three beat the teen to the ground, where his iPod (search) and sunglasses fell out — and were then scooped up by his attackers, the source said.

The beating left the teen, who apparently did not fight back, with "substantial pain and bruising," as well as a cut near his eye, the criminal complaint says. The victim apparently reported the attack to cops, who arrested the girls at the school about an hour later.

The three were arraigned on Saturday on robbery charges and released on their own recognizance. They face up to 15 years in prison if convicted.

Lawyers for Wiest and Rucinski did not return calls for comment, and Zieden's lawyer could not be reached. The headmaster of the Beekman School did not return a call.

The case is being prosecuted by the Manhattan District Attorney's Office — a place Wiest would have some sway in the land of make-believe. She played Manhattan DA Nora Lewin for two years on the TV court drama "Law & Order." Wiest's career has also seen her play the role of a mother to troubled kids, most notably in the horror flick "Lost Boys" and the Ron Howard comedy "Parenthood."

The 57-year-old actress is best known for her work with Woody Allen and has won Best Supporting Actress Oscars for roles in two of his films, "Hannah and Her Sisters" and "Bullets Over Broadway."

She's currently appearing as the voice of "Mrs. Copperbottom" in the hit animated movie "Robots."

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