A 22-year-old woman has died after she was set on fire near Hyderabad yesterday by a former colleague who was allegedly obsessed with her and had been stalking her. Sandhya Rani, a receptionist for a company in the Secunderabad area, was on her way home from work around 6.45 pm when Karthik came on a motorbike and stopped to speak to her. They had worked together about two years ago.