CHICAGO (CBS) — Allegations were coming to light on Tuesday against the principal of a Chicago public school in the Pilsen neighborhood.

As CBS 2’s Mai Martinez reports, Josiah Pickard Elementary School principal Rigo Hernandez has been in charge for five years, during which time dozens of complaints have been filed against him.

Hernandez was eager to talk about the allegations and defend himself against those complaints on Tuesday, but when he arrived at school Tuesday morning, he said his bosses wouldn’t let him discuss the matter publicly.

The teachers who made the allegations and the Chicago Teachers Union, however, had plenty to say.

Some teachers, past and present, have painted an ugly picture of what happens inside the school.

“He was ranting about something and then made a threat to us that, if we went to his supervisor, he was going to cut our throats,” teacher Marlene Chavez said.

Chavez has filed several grievances and complaints with the Illinois Educational Labor Relations Board against Hernandez.

She’s not alone. According to the Chicago Teachers Union, 31 grievances have been filed against Hernandez since 2008.

“Allegations of threats of physical violence; we have assaults and batteries,” said CTU representative John Kugler.

He also said there are allegations of sexual harassment.

“He tends to make sexual comments about teachers’ cleavage, or their hips. He rates teachers,” Chavez said. “Who’s pretty, who has nice hips.”

She said the harassment makes her apprehensive every day when she heads to work.

“It’s really scary, because I don’t know if he’s going to come out of his office and scream at me, yell at me,” she added.

It’s a fear shared by some of Chavez’s former colleagues.

One woman, who asked to remain anonymous, said it was difficult working for Hernandez.

“I wasn’t sure from one day to another if he was going to yell at me,” she said.

When asked if it’s normal for a principal to have the volume of complaints Hernandez has, Kugler replied “Absolutely not.”

CPS officials would only confirm investigating one allegation against Hernandez, and would not say which one.

In a statement CPS said “Chicago Public Schools takes every claim of unsafe and unfair workplace practices seriously and, when appropriate, thoroughly investigates them. We are committed to ensuring fairness and equity for all staff members so that every employee can work in a safe and secure environment. In the case of the allegation against Mr. Hernandez, our investigation found that the allegation was not substantiated by the evidence. Mr. Hernandez met the conditions specified in the resolution and no further action was necessary.”

As for Hernandez, he denied any wrongdoing and, in his words, Chavez is “just throwing spaghetti at the wall to see what sticks.”

Chavez, who until recently was the union delegate at the school, said Hernandez is trying to fire her because of her complaints. Hernandez said it’s because her work is unsatisfactory.