The students went to the residence of 57-year-old teacher Rita Biswas at Netaji Subhas Colony yesterday on the pretext of taking tuition and stabbed her in the stomach when she opened the door, Deputy Superintendent of Police Shashi Bhusan told reporters here.
The victim was declared brought dead by the doctors at the Sadar Hospital, he said, adding she was a teacher with the St. Joseph School.
Victim's 64-year-old husband, Asish Kumar Biswas, was admitted to the hospital with injuries he suffered while trying to resist the attackers, the police officer said.
"The matter is still under investigation," he said when asked whether the students were of the same school and what could have been the reason for the crime.