BOSTON — "We are unapologetic in our commitments to supporting all menstruators regardless of their gender identity," the organizers of "Trans Period Pride" wrote Wednesday in a defiant Instagram statement announcing the event would go on at an undisclosed downtown venue with Boston Police providing security after a wave of online threats.

The women's group Mass NOW and the Massachusetts Transgender Political Coalition — the two organizations behind the event — said the June 17 gathering will proceed despite the Boston Public Library's decision last week to cancel the original Copley Square booking after a week of mounting national backlash. The new venue has not been disclosed publicly. The event will run from 6 to 8 p.m.

"Let us be clear: we are not backing down, we're doubling down," the groups wrote in a four-slide post, calling the past week "an unacceptable wave of anti-trans hatred and misinformation."

The organizers said the Boston Police Department will be on site at the event because of the severity of threats received, and that they were coordinating with the Boston Mayor's Office of LGBTQIA2S+ Advancement — which co-sponsored the original BPL event — on safety protocols and "plans to handle any disruptions that may occur."

The two groups defended the substance of the event, which they said was meant to "shed light on the specific challenges, stigmas, and misconceptions that transgender people who menstruate face in an affirming, intimate community space."