Hunter Pollack, brother of Parkland school shooting victim Meadow Pollack, is calling out the Broward Teachers Union for mocking him and others who are speaking up about mismanagement in the district.

Hunter and his father, Andrew Pollack, as well as parents of other students who died in the February school shooting, are exposing the problems and bad policies that contributed to the death of 17 Marjorie Stoneman Douglas High School students, and the broken promises to prevent a similar tragedy.

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The bulk of the frustrations have been directed toward Broward County School District Superintendent Robert Runcie for firing an independent investigator who was looking into the shooting and the failure to install metal detectors at schools this year, as promised, CBS reports.

But Hunter has also pointed to the Broward County teachers union as part of the problem, and some aren’t taking kindly to the criticism.

Townhall reports:

He was in an online exchange with a few of the members on Monday regarding a baseball coach and security monitor who had been accused of sexual harassment, when one of them, Valter Meranda, started to mock his appearance.

“Why is his head so square?” Meranda posted. “Isn’t that a condition?”

Hunter posted the conversation online and the reaction was fierce.

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“.@BrowardTeachers union members making fun of the shape of my head and criticizing my dad for being mad about Andrew Medina sexually harassing his baby girl. We need to take back the Broward School board August 28th,” he wrote.

“Members of the @BrowardTeachers union were making fun of my son @PollackHunter’s head on Facebook.. Seriously? What the hell is wrong with these people? @RobertwRuncie these are the kind of people you hire?” Andrew Pollack wrote. “Pathetic. #FixIt”

“First, the teachers/union members making those comments should be fired for bullying. Secondly, you’re a nice looking young man trying to make a difference. Maybe they should give that a try,” Gail Goodwin posted.

“This is disgraceful talking about a child who was murdered under their watch,” Natalie Hilden added.

“What the actually f#@k is wrong with these people??? This is crap is beyond despicable,” Jessica Hamel wrote. “They are awful people.”

“I’m having a hard time not spewing forth a string of expletives,” Scott Howard added. “The absolute disdain for a family that lost a loved one is infuriating.”

Hunter also issued a statement to Townhall that put the issue in perspective.

“The teachers in Broward County deserve so much better than the leaders of their union. If you talk to union leaders privately, they’ll admit that the district’s discipline policies allow teachers to be essentially abused by kids while administrators look the other way,” he told the news site. “But if you ask them publicly, they’d sooner verbally abuse a kid than defend their own members from administrators.

“It’s so sad, because teachers deserve so much better.”