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MASSACHUSETTS, March 31, 2017 (LifeSiteNews) – The "Free Speech Bus" promoting biological differences between males and females was vandalized at all three stops it made in Massachusetts yesterday. Protesters smashed the vehicle's tail light, threw meat and coffee at it, wrote on it with Sharpie, and scratched it with keys.

The bus was back on the road after repairs following an attack on it in New York City.

The "Free Speech Bus" is a project of CitizenGO, the National Organization for Marriage (NOM), and the International Organization for the Family.

NOM's Joe Grabowski told LifeSiteNews that a protestor at Boston City Hall threw a full cup of Dunkin' Donuts coffee through the open front door of the bus. In response to the presence of the bus, Boston Mayor Marty Walsh raised a flag symbolizing transgenderism to "support the LGBTQ community," a local ABC affiliate reported.

"When you deny the experience of transgender individuals, you are denying the experience of basic human civil rights," said Walsh.

Boston stands for love & acceptance. At 12:30pm, please join me as I raise the transgender flag on City Hall Plaza in a show of solidarity. — Mayor Marty Walsh (@marty_walsh) March 30, 2017

Then, at the Massachusetts statehouse, "transgender protestors [were] trying to block us from proceeding forward" and "pounding with their fists on the side of the bus," said Grabowski. "One of them at that stop duct-taped a used condom to the side of the bus."

"We believe it was at that location that one of them punched or somehow used an object to shatter a tail light," he said. "The police had to get involved there in order to secure us our right of way."

A video recap of the day from the bus organizers shows a police officer addressing a masked male protestor as "sir," asking him to stop blocking the bus. Local media also captured this.

"I am not a 'sir'!" he shouted. "I am not a man or a woman."

It was in Cambridge, just outside of Harvard University, that the protests "got ugliest," said Grabowski. "They keyed the side of the bus, scratching it up."

People also wrote pro-transgender messages in Sharpie on the side of the bus.

Then, "they began throwing sandwiches at bus" and "putting lunch meat into the windshield wipers."

"Roughly 30 Harvard students and Cambridge residents protested the arrival of an anti-transgender 'free speech' bus on Harvard’s campus Thursday afternoon," the student paper reported. "Protesters scrawled in permanent marker over the bus’s lettering with the words 'HATE SPEECH BUS,' as well as, 'Hate is not welcome here.'"

When news broke that the bus would be stopping by Harvard, the prestigious university's "BGLTQ office" hung a "Trans Lives Matter" banner, signed by students and faculty, in the Science Center Plaza. One student, Lily Velona, blasted the conflation of "free speech" and "hate speech" in statements to the Harvard Crimson.

"Hate speech is not protected speech," she said. "It’s not free speech. No one has the right to use hate speech."

The protestors' actions "prove the point that what is happening to the bus is what happens to everyday people when they express in their workplace or in their school or local government any concerns that they have about [transgender] bathroom policies," said Grabowski.

Those concerned about bathroom privacy and "legal or workplace regulations that are being put in place" have their concerns labeled "transphobia," he said. "They’re intimidated and shouted down. And that’s why we’re out here on the road, because those people deserve a fair hearing and they deserve to be treated with respect. We want respect on both sides of the debate."

But Grabowski says he's not angry with the protesters, and that his response is one of compassion.

"I think that there’s a lot of pain," he said. Many people are upset or have strong emotions about the issue and "we respect that, we understand that."

But there are "victims on the other side that don’t get spoken about," he continued. "People who feel that their privacy is being invaded" and that "their religious beliefs and such are being pejoratively represented."

The Free Speech Bus also inspired someone to make a video game in which users vandalize the bus.

"In 'Ignorance Fighter II' — based off the classic martial arts game 'Street Fighter II' — players can punch and kick a rendering of the Free Speech Bus until the tires and windows fall off," the Washington Post reported.

"I can understand how people might be concerned about that in the context of actual violent attacks being made against our bus" and the "very violent threats being made online," said Grabowski. "Making such a video game is arguably irresponsible."

"On the other hand, I would say that’s a legitimate exercise of free speech, to make a video game in which you can through an avatar express safely and without actual violence...your disagreement with something," he continued. "And I would contrast that to actually, physically attacking someone else’s property, physically threatening someone else. That’s when it crosses a line."

"I think it’s kind of a stupid game," he added, but its creator is "within his rights to do that."

The Free Speech Bus is finishing up a tour of the East Coast.