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Hilary Swank has refused to release details of who benefited from her controversial attendance at Chechen President Ramzan Kadyrov's birthday party.

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The Oscar-winning actress issued an apology in October amid a storm of criticism of her presence at the event, and she promised to hand her personal appearance fee to charity.

Exiled former Chechen leader Akhmed Zakayev has written to Swank, demanding she provide details of her payment and the charities she's handed it to.

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A spokeswoman for the actress tells The Hollywood Reporter, "Over the last four months, Hilary has been working directly and privately with various human rights organizations and other charities, giving both her time and financial resources. At the request of such organizations, and consistent with Hilary's longstanding practice of donating anonymously, she will not be publicly acknowledging her contributions and efforts."

Swank was slammed by officials at Human Rights Watch for partying with Kadyrov in October amid claims he is responsible for torturing his citizens.

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