In a 12-month span, in 2015 and 2016, Pune had witnessed four incidents of unidentified persons sending packets containing explosive substances and detonators by post. All four cases remain unsolved. In July 2015, a packet containing an explosive substance, a detonator and paper cuttings of Sanatan Prabhat, the mouthpiece of Sanatan Sanstha, was sent to Ajay Bhosale, then state convenor of Sambhaji Brigade. The Brigade had come to the limelight in January 2004, when its activists vandalised the Bhandarkar Oriental Research Institute (BORI) over a book written by American writer James Laine on Maratha King Shivaji.
A week later, another packet with explosive substances, a detonator and paper cuttings of Sanatan Prabhat were sent to Santosh Shinde of Sambhaji Brigade. In May 2016, the office of the director of Film and Television Institute of India (FTII) received a live detonator, along with an explosive substance, and a threat letter warning against any association with Kanhaiya Kumar, a student leader of the Jawaharlal Nehru University.
After two days, a similar India Post parcel, containing a live detonator and an explosive, was found at the Department of Communication and Journalism of the Savitribai Phule Pune University (SPPU). The investigations into the four cases have not led to any concrete results till now, said Pune City Police officials.