First proper revolutionary secret society known as Anushilan Samiti (Calcutta) was founded on 24 March 1902 by Pramath Nath Mitra better known as P. Mitra.
The people associated with this samiti were Sri Aurobindo , Deshabandhu Chittaranjan Das, Surendranath Tagore, Jatindranath Banerjee, Bagha Jatin, Bhupendra Natha Datta, Barindra Ghosh etc.
Out of them Bhupendra Nath Datta was brother of Swami Vivekananda. Barindra Ghosh was sent to Paris to learn the science of Bomb Making and here he came in touch were Madam Kama. Madam Kama was already associated with the India House and the Paris India Society.