NEW YORK, New York, March 23, 2017 (LifeSiteNews) – Vandals sprayed paint, used a hammer to smash, and broke the window of a "Free Speech Bus" on a tour fighting gender ideology this afternoon.

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

"It's biology: boys are boys...and always will be. Girls are girls...and always will be" is the message of the bus.

"The bus was on the streets of New York" in Manhattan shortly after 4:00 p.m. today, Joe Grabowski of the National Organization for Marriage told LifeSiteNews. "It was vandalized by spray paint and a hammer was taken to it on the side."

He said police are at the "crime scene" investigating.

“This is what those who pretend to preach tolerance actually feel about…other viewpoints," said Graboswki. "We’re the ones who try to have an open conversation and a dialogue with people and this is the kind of intimidation that is used to try to cow people who believe in traditional values not to speak out."

The bus tour organizers are considering it a "hate crime," according to an email from NOM President Brian Brown.

Grabowski said it was ironic that opponents of the bus claimed it would incite violence against people who identify as transgender.

"Well, here’s the first act of violence that we’ve seen," he said. "And it’s not somebody out there attacking a trans person. It’s us getting attacked."

Some twitter users cheered the destruction of the bus.

.@CitizenGO Bring your creepy hate bus to Boston. We'll set fire to it there, too. #FreeSpeechBus — Ba-wyan White (@CinemaSuicide) March 23, 2017

Hey #FreeSpeechBus: Free Speech means you're legally allowed to say hateful bullshit. It does NOT mean you're free from the consequences. https://t.co/b2xYf6zLjC — negative zero (@rigatonimonster) March 23, 2017

whoever vandalized the #freespeechbus in NYC, feel free to DM me so i can buy you a beer next time i'm in town — Jamey Lovelace ���� (@jameybash) March 23, 2017

@ProFam_Org I love how you call it the #freespeechbus yet that is the opposite of what it is. I'm glad it was vandalized. — TaylaKrueger (@TaylaKrueger) March 23, 2017

Grabowski said the bus tour organizers encourage any witnesses to come forward.

The bus was parked outside the United Nations earlier. It's scheduled to visit other cities on the East Coast.