Dehra Dun: The police are investigating a letter an “ISI agent” has sent to an employee of Indian Military Academy (IMA) here threatening to blow up his house if he does not “work” for the agency. Senior Superintendent of Police (Dehra Dun), Abhinav Kumar, said this could be a case of personal enmity, but police are investigating the matter on all angles.

A copy of the letter, which was received on Friday, had been handed over to the police, he said.