The school building. (Anindya Shankar Ray)

A Class VIII student ran out of his classroom and jumped off the third-floor balcony on Wednesday afternoon while a teacher was conducting a straw poll among his classmates to determine whether the boy had written a letter using obscenities.

The 13-year-old landed on the concrete courtyard of Nopany High School in Girish Park but miraculously escaped with only a fracture in his heel and broken nose.

The boy is now in the ICU of Apollo Gleneagles Hospitals, off the EM Bypass. Doctors said he was out of danger.

A classmate had complained to economics teacher Deepa Saha accusing the boy of writing an indecent letter. Saha called class teacher Ashok Singh, who took the boy to principal Srabani Sinha. She said she had asked Singh to question other students to confirm if the boy was guilty.

“A student who was in the corridor said he had seen the boy jump over the 4ft high railing,” said Singh.

According to a child psychologist, the boy may have jumped to avoid imminent humiliation. The language that he allegedly used is common among teenagers, he added.

“The boy is very naughty. The school counsellor had several sessions with him. We also tried to counsel him and failed. On Tuesday, the history teacher had summoned his parents. On Wednesday, we were making an inquiry when he jumped,” said Sinha.

The boy’s father, who runs a confectionery outlet in north Calcutta, was too distraught to speak.

The boy’s uncle said: “We do not yet know whether he fell or jumped. Right now our priority is ensuring that he is treated properly.”

An officer of Girish Park police station said they had started a probe though no complaint had been lodged.