As many as 18 students suffered bruises and developed swelling on their hands after they were caned last evening, a police official said.
"The students of the school situated on the Station Road were preparing for their annual day function yesterday. In the process, the students were shifting benches in a class room. The trustee, who resided in the same building where the school is located, was disturbed by the noise in the class room," Thane Nagar police station inspector Mandar Dharmadikari said.
No arrest is made so far.
The trustee has been booked under section 324 (voluntarily causing hurt by dangerous weapons or means) of the IPC, Dharmadikari said.