(CNN) -- Three former women's head coaches with the University of Minnesota-Duluth are suing the school, alleging discrimination under Title VII and Title IX and saying they were fired because they are female and gay.

Two of the plaintiffs suing the Board of Regents say they were fired also because they are Canadian, and two of them claim age discrimination because they are older than 40.

Shannon Miller, Jen Banford and Annette Wiles all left the school in the past year after suffering what they describe as a pattern of hostility and making complaints that went unanswered.

In a statement, University Chancellor Lendley Black said the school refutes the allegations and claims of discrimination and will "aggressively defend" itself in the lawsuit.

"UMD continues its focus and commitment to diversity, equality and inclusion, and I am personally committed to continuing an environment where diversity is embraced," Black said.

The case was filed Monday in U.S. District Court in Minnesota.

Miller, 51, was the head coach of women's hockey until December, 9, 2014, when the university informed her it would not renew her contract.

She says the university's chancellor and athletics director told her the decision was "strictly financial," but she says she was already paid 30% less than the men's hockey coach and was never asked to take a pay cut.

Miller was the former head coach for the Canadian women's hockey team that took the silver medal at the 1998 Winter Olympics in Nagano, Japan. During her 16 seasons at the university, she coached the team to five national championships.

Head women's softball coach Jen Banford, 34, was notified December 11, 2014, that her contract would not be renewed. She says it was because of her support for Miller, who had been let go two days earlier, and because she is an openly gay Canadian woman.

Both Banford and Miller, who is a dual Canadian-U.S. citizen, say university officials regularly expressed hostility toward Canadians and made derogatory remarks in violation of Title VII of the Civil Rights Act, which prohibits discrimination on the basis of sex or national origin.

While head coach for women's softball, Banford was also part-time director of operations for the women's hockey program. She says the university in January offered to retain her as head softball coach, but at a lower salary, an offer she declined because of the alleged discrimination and harassment.

Wiles, 46, was the head women's basketball coach until she says she was forced to resign June 1, 2015, because of "the hostile and discriminatory environment created by the university." She coached for seven seasons at UMD, taking the team to the playoffs twice.

She said Intercollegiate Athletic Director Josh Berlo's hostility began in 2013 after she invited him to attend a campus luncheon for the GLBT National Coming Out Day, where she planned to come out as a lesbian. He and Assistant Athletics Director Abbey Strong soon began shunning her and excluding her from meetings, she says, helping to create a hostile environment that spread throughout the Athletics Department.

CNN's Drew Iden contributed to this report.

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