Updated at 6:00 p.m. ET

The union representing opera performers, choral singers and dancers says that according to an independent investigation it commissioned, opera megastar Plácido Domingo engaged in "inappropriate activity" with women both "in and outside of the workplace."

In a brief press release issued early Tuesday, American Guild of Musical Artists gave no information about specific incidents of alleged misconduct, except to say that it ranged from "flirtation to sexual advances, in and outside of the workplace" nor did the union provide any time span for those activities. The release continued: "Many of the witnesses expressed fear of retaliation in the industry as their reason for not coming forward sooner. The AGMA Board of Governors has accepted the findings of the report and will take appropriate action."

The investigation was launched last September. Two sources tell NPR that its conclusion was to include a $500,000 settlement between the singer and AGMA. But, the sources say, the settlement was retracted overnight after The Associated Press published some details about the investigators' findings early Tuesday.

The AP reported that the investigators hired by AGMA spoke to 27 people who said that they were either "sexually harassed or witnessed inappropriate behavior" over the course of two decades and that the timeline of Domingo's behavior included the periods during which he was artistic director at Washington National Opera and general director of LA Opera. One of NPR's sources who saw the investigators' report confirmed the total number of alleged victims and witnesses, as well as the time frame of the misconduct.

The 79-year-old singer issued a statement Tuesday that said in full: "I have taken time over the last several months to reflect on the allegations that various colleagues of mine have made against me. I respect that these women finally felt comfortable enough to speak out, and I want them to know that I am truly sorry for the hurt that I caused them. I accept full responsibility for my actions, and I have grown from this experience. I understand now that some women may have feared expressing themselves honestly because of a concern that their careers would be adversely affected if they did so. While that was never my intention, no one should ever be made to feel that way. I am committed to affecting positive change in the opera industry so that no one else has to have that same experience. It is my fervent wish that the result will be a safer place to work for all in the opera industry, and I hope that my example moving forward will encourage others to follow."

The AGMA investigation, as well as a separate independent investigation led by LA Opera, was launched after the AP last year reported accusations of 20 women who said that Domingo had sexually harassed them as far back as the 1980s and as recently as the 2016-2017 opera season.

In a statement issued Tuesday, the two Domingo accusers who have come forward by name — singers Patricia Wulf and Angela Turner Wilson — urged AGMA to drop Domingo's membership from the union. "Even though the industry failed to protect us from misogynist and predatory behavior, an expulsion from the union would signal that the industry is learning from its mistakes and that sexual harassment and abuse — perpetuated by industry complicity — will not be tolerated in the future."

In the same statement, the two women's lawyer, Debra Katz, who also represents other Domingo accusers, urged AGMA to release the results of its investigation, saying: "Opera companies may have prioritized ticket sales generated by powerful men over the safety of women in the industry, but the AGMA now has an opportunity to send a clear message that the safety and dignity of women matter. We look forward to the release of the final report."

Several prominent American companies, including most notably the Metropolitan Opera, parted ways with Domingo in the wake of the accusations. By contrast, many European opera houses and singers either offered him public support or suggested that they would await the results of the investigations.

Speaking anonymously for fear of retribution, the sources with knowledge of the planned $500,000 settlement told NPR that Domingo's legal team withdrew its settlement offer with AGMA early Tuesday morning. NPR has viewed the email which senior AGMA leadership sent early Tuesday to its officers and national board of governors, a group of about 80 individuals, saying that the union intends to take "appropriate action" against any members who had spoken to the AP, adding: "The damage caused by these individuals to our union, our members and the targets of Domingo's harassment is incalculable." AGMA declined to comment to NPR on details of the tentative settlement or its withdrawal.

The results of the AGMA investigation were not supposed to be disclosed, either in summary or in full, to the public or to the union's membership. Union leaders, however, were permitted to speak individually to members about the investigation and its findings.

Funds from the settlement were supposed to cover AGMA's fees for the investigation, to fund a sexual harassment prevention training program for AGMA's membership and possibly also to be distributed in part to a variety of organizations that aid survivors of sexual misconduct and abuse.

In its Tuesday public statement, AGMA said that the union and its signatory performing arts companies plan to "improve culture" and "prevent harassment in the future." Additionally, AGMA said it will conduct a promotional campaign and use training programs "to empower its membership to speak out and prevent harassment."

The separate investigation launched by LA Opera, where Domingo was general director for 16 years before resigning last October, is ongoing.

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