Packirisamy of the school at Sethur village was arrested last night based on a complaint by the five-year old girl's parents.
The child had returned from the school unwell on August 18 evening and when her parents enquired with her she told them about the teacher's assault.
The parents approached the school management the next day. As the school administrator reportedly did not initiate any action, they lodged the complaint with police, who after inquiry arrested Packirisamy.
Karaikal North Superintendent of Police Marimuthu and other officials held talks with the agitating people and assured action following which they dispersed, police said adding further investigation was on.