S Ramya taught Maths to students of Class 5 at Gayathri Matriculation School.

A 23-year-old teacher was hacked to death by a man in a private school in Tamil Nadu's Cuddalore district, around 200 km from Chennai.

S Ramya who taught Maths to students of Class 5 at Gayathri Matriculation School was alone in her classroom when the suspect Rajashekhar targeted her.

"She used to come early to the school as her home is nearby. We understand there was an argument after which he had killed her," said an official.

Police suspect that refusal of marriage proposal could be the reason behind the attack.

"The suspect Rajashekar had known the teacher from college days. Six months ago, he had asked her parents to marry their daughter with him, but they had refused. This appears to be the motive behind the attack," a senior police officer told NDTV.

Police also said that Rajashekhar had messaged his sister that he would commit suicide.

The teacher's body has been sent for post-mortem.