Shocking conversations allegedly recorded at a primary school have led authorities in southwestern Poland to look into claims that a teacher taped small children's mouths shut to silence them.

A suspicious mother of a 6-year-old secretly recorded a day's classes of the teacher, identified only as Justyna G.

In the recordings published by TVN24, a woman is heard threatening that she will again put adhesive tape over a child's mouth. "But it hurt," a small child is heard pleading.

The woman's voice also says "I will take your tapes off during breakfast," as children's voices can be heard in the background.

Agnieszka Cichorek, the director of the village school in Szczodre, said she was not aware of the teacher's behavior, and the teacher has since been fired.

"I don't think this person should work with children," Cichorek said.

Janina Jakubowska, a spokeswoman for the education authorities, said Tuesday that regional school inspectors are gathering facts in the case. Prosecutors and local administration officials are also investigating.

"We are checking every report of abuse: the shouting, the tape on the mouths," Jakubowska said. "We are checking the qualifications and the supervision practices."

Psychologist Maria Berlinska said on TVN24 that she did not believe this was an isolated case and stressed that the practices and the atmosphere at a school largely depend on the director.