The FBI has confirmed that an investigation has been launched after three members of Super Happy Fun America, the organization behind Boston’s upcoming Straight Pride Parade, were sent glitter-filled envelopes in the mail this week.

“The envelope immediately struck me as different. There was no return address, and it was taped around the edges, as if they didn’t want anything to fall out,” Samson Racioppi, one of the organizers, told NBC News. “I pinched the bottom and felt this granular substance.”

The granular substance he felt was glitter, according to Lt. Robert Roy of the Salisbury Police Department. Roy also said the envelopes included Bible verses with “Happy Pride” signed in rainbow colors. One of the verses, Psalms 86:15, states, "But you, Lord, are a compassionate and gracious God, slow to anger, abounding in love and faithfulness.”

“Glitter bombing” — covering someone in colorful glitter — has historically been used as an act of protest against those who oppose LGBTQ rights. Former House Speaker Newt Gingrich was famously glitter bombed in 2011 by a protestor who yelled: “Feel the rainbow, Newt! Stop the hate! Stop anti-gay politics."

However, the organizers of the Straight Pride Parade, which is scheduled for Aug. 31, maintain that they are “not anti-gay,” just simply “pro-straight.”

After receiving the “suspicious” envelope, Racioppi said he immediately alerted other members of Super Happy Fun America. That’s when he discovered that John Hugo and Mark Sahady, the president and vice president of the organization, respectively, had each received similar mailings. Hugo, a Republican who unsuccessfully ran for Massachusetts' 5th Congressional District in 2018, urged Racioppi to call police.

“With all of the controversy surrounding my activism, I’ve had to make numerous police reports,” Racioppi said. “They know me at this point.”

After Racioppi alerted the authorities, bomb squads were sent to the Massachusetts towns of Woburn, Salisbury and Malden. Hugo, who called the mailings an “act of domestic terrorism,” said he had also alerted conservative firebrand Milo Yiannopoulos, the grand marshal of the upcoming Straight Pride Parade, though it does not appear Yiannopoulos was sent a glitter-filled mailing.

While the investigation is ongoing, FBI spokeswoman Kristen Setera told NBC News, “There is no threat to public safety.”

Hugo, however, maintains he still doesn’t know what the contents of the envelope are. “Even if it’s just baby powder,” he added, “I want to see this person prosecuted.”

The Straight Pride Parade was first announced in early June, at the beginning of LGBTQ Pride month, to great controversy. Actor Brad Pitt threatened legal action after Super Happy Fun America used his picture and advertised him as the parade’s mascot without his permission.

Many have deemed the event homophobic, viewing it as a step backward in Massachusetts, which in 2004 became the first state to legalize same-sex marriage. Boston Mayor Marty Walsh has criticized the event, though he stated that the city cannot deny permits based on personal beliefs.

Whatever outside groups may try to do, he said, "our values won't change."

"I invite each and every person to stand with us, and show that love will always prevail,” Walsh wrote on Twitter.

Some of the parade organizers have been linked to far-right and white nationalist groups. Sahady has a history of organizing and participating in events hosted by Resist Marxism, a conservative activist group dedicated to "American nationalism" and defending "the Constitution from violent extremists and the regressive left,” along with the New Hampshire American Guard, an organization that has been labeled a white supremacist group by the Anti-Defamation League.

Yet the Straight Pride organizers claim they are “inclusive of all, including LGBTQ people,” asserting that they have a “gay ambassador who challenges heterophobia” on their team.

“We want to take back the public square. This is about free speech,” Racioppi said. “It’s perfectly natural and normal to celebrate heterosexuality, and the parade is not being held at any expense to the LGBTQ movement.”

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