Bengal Volunteers was an underground revolutionary group against the British rule of India.The group was functional from its inception in 1928 to the Indian independence.
Subhas Chandra Bose organised a group of volunteers during the 1928 Kolkata session of Indian National Congress.The group was named Bengal Volunteers and was under the leadership of Major Satya Gupta. Subhas Chandra Bose himself was the GOC. After the Calcutta session of the Congress was over, the Bengal Volunteers continued its activities. Soon, it was turned into an active revolutionary association.
It should be noted that the Irish Volunteers, founded in 1913, had been prominently involved in opposing British rule in Ireland, and that this then-recent connotation of the term "Volunteers" would have certainly been known to politically-involved Indians opposing British rule in their own country.
Bengal Volunteers decided to launch 'Operation Freedom' in the early 1930s, primarily to protest against the police repression in different jails in Bengal.
In August 1930, the revolutionary group planned to kill Lowman, the Inspector General of Police who was due to present in the Medical School Hospital in Dhaka to see an ailing senior police official undergoing treatment. On 29 August 1930, Benoy Basu who was a student of the Medical School, casually clad in a traditional Bengali attire, breached the security and fired at close range. Lowman died instantly and Hodson, the Superintendent of Police, was grievously injured. Later on Benoy Basu managed to escape to Kolkata from Dhaka
The next target was Col N.S. Simpson, the Inspector General of Prisons, who was infamous for the brutal oppression of the prisoners in the jails. The revolutionaries decided not only to kill him, but also to strike terror in British official circles by launching an attack on the Secretariat Building - the Writers' Building in the Dalhousie square in Kolkata.
On 8 December 1930, Benoy Basu along with Dinesh Gupta and Badal Gupta, dressed in European costume, entered the Writers' Building and shot Simpson dead.