Mystery shrouded the body of a 25-year-old nurse of Apollo Gleneagles Hospitals' nursing complex at Narayanpur, Rajarhat, after an autopsy revealed that an unidentified lethal medicine injected in her body was found.

Baguiati Police began an investigation following the autopsy report after the corpse of Sanisha Mall, a resident of Kerala, was found in her hostel room on February 23. The room was shared by four other nursing staff but when the body was found covered by a quilt, no one was present .

Police were trying to ascertain whether the victim herself pushed the lethal injection or somebody did it. Police seized the victim's mobile phone and were verifying the call list.