The severely burnt girl, Nusrat Jahan Rafi, 18, is undergoing treatment at the National Institute of Burn and Plastic Surgery in Dhaka Medical College Hospital.
Police detained a teacher and a student for questioning over the incident at Sonagazi Islamia Senior Fazil Madrasa on Saturday morning, Sonagazi Police Station Inspector Md Kamal Hossain told bdnews24.com.
The followers of Siraj threatened the family to withdraw the case, Noman alleged.
Nusrat, daughter of AKM Musa from Charchandia village under Sonagazi Municipality, went to the madrasa on Saturday morning to sit for Alim exams, equivalent to HSC.
“Some students called her to the roof and threatened her to withdraw the case. They set fire to her after pouring kerosene on her when she refused to withdraw the case,” he said.
Nusrat suffered an 80 percent burn on her body, according to Abu Taher Bhuiyan, a physician at the Feni hospital.
She was later sent to Dhaka for better treatment, the doctor said.