While in the college, Sen was drawn into the revolutionary activities of the Indian Republican Army, led by
Surya Sen. Once he broke the safe of his uncle to raise funds for the revolutionary cause. Sen played an active part during the Chittagong Armoury Raid. He sabotaged the transport in
Chittagong before the raid. He was sentenced to life imprisonment for his involvement in the incident and deported to the Andaman. After spending sixteen years in the Andaman Cellular Jail and other jails, he was finally released on parole from Dhaka jail in 1946. == Death ==