Presidential candidate Gov. Chris Christie (R-N.J.) lambasted teachers unions on Sunday.
"At the national level, who deserves a punch in the face?” CNN's Jake Tapper asked the New Jersey governor during an interview. The question was a callback, he said, to Christie's affinity for saying during his first term that "you can either sidle up to [bullies] or you can punch them in the face."
"The national teachers union, who's already endorsed Hillary Clinton, 16, 17 months before the election," Christie replied.
Christie was ostensibly referring to the American Federation of Teachers -- the second largest teachers union in the country -- which endorsed Democratic presidential candidate Hillary Clinton in July.
"They’re not for education for our children," he said. "They’re for greater membership, greater benefits, greater pay for their members. And they are the single most destructive force in public education in America."
Christie has had a hostile relationship with teachers unions since the start of his gubernatorial tenure. In January 2010, before he was sworn in, Christie said teachers unions "are back in the 19th century in terms of their thinking." He has publicly sparred with individual teachers on a number of occasions.
The New Jersey Education Association -- the state's largest teachers union -- did not take the governor's words lightly. On Sunday, the group called on Christie to resign.
"Chris Christie's instinct is always to threaten, bully and intimidate instead of build consensus and show true leadership," NJEA President Wendell Steinhauer said in a statement.
Randi Weingarten, president of the AFT, said in a statement that Christie's interview reflects a "sad day in the life of our nation to see a candidate threaten violence to gain political favor."
"That [Christie] would threaten to punch teachers in the face -- mostly women seeking to help children meet their potential and achieve their dreams -- promotes a culture of violence and underscores why he lacks the temperament and emotional skills to be president, or serve in any leadership capacity," her statement said.