“It hurt,” The A.P. quoted Ms. Wilson as saying. “It was not gentle. He groped me hard.”

Ms. Wilson won Washington’s Artist of the Year award that season but was not rehired, The A.P. reported, saying that she attributed that to her interactions with Mr. Domingo. The news service said that she had told her husband and parents of the groping contemporaneously and written about Mr. Domingo’s unwanted attentions in a journal she kept at the time, but that a makeup artist she believed had witnessed what happened said he did not recall it. Ms. Wilson went on to sing elsewhere, including at the Dallas Opera, and to teach. She is one of 11 women who shared their experiences with the news agency after its initial report of allegations against Mr. Domingo.

A spokeswoman for Mr. Domingo, Nancy Seltzer, disputed the allegations.

“The ongoing campaign by The A.P. to denigrate Plácido Domingo is not only inaccurate but unethical,” she said in a statement, which was sent to the news agency and then to The New York Times. “These new claims are riddled with inconsistencies and, as with the first story, in many ways, simply incorrect. Due to an ongoing investigation, we will not comment on specifics, but we strongly dispute the misleading picture that The A.P. is attempting to paint of Mr. Domingo.”

[Read about how the allegations against Mr. Domingo have divided the opera world.]

The Dallas Opera announced its cancellation on Twitter Thursday, posting a statement in which it said it had decided to cancel the gala “in light of ongoing developments regarding allegations made against Plácido Domingo.”

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