The beheaded body of a 12-year-old student was found inside the hostel of a madrasa in Chachar district of Assam on Sunday, police said.
A senior official said the incident took place at Darus Salam Hafizia madrasa in Dholai area, and his body was noticed by one of the six roommates.
'There were seven students, including the deceased, inside the hostel room. His roommate saw the beheaded body when he woke up in the morning,' the official said.
The body has been sent to Silchar Medical College and Hospital for post-mortem.
Cacher SP and other senior officials visited the spot and started an investigation.
'We have already detained three people, including students of the madrasa, for questioning. Statements of other students are also being recorded,' the official said.
The institute has been sealed by the authorities pending investigation of the case, police said.