Nandalal Bannerjee was a much hated name among the ardent Nationalists, but is mostly unknown to folks outside Bengal. He was the police inspector who caught Prafulla Chaki, one of the co-accused along with Khudiram Bose in the attempt to kill the magistrate Kingsford. Chaki trusted Bannerjee who befriended him to extract information until he could hand him over to the British police and get a promotion or a hike. Chaki was disheartened by the betrayal - "you being a Bengali handed over a fellow Bengali? How could you?" Then he committed suicide rather than handing himself up in Mokamghat Junction, where a large police force was waiting for him, being tipped off by Nandalal. Nandalal was given a raise, but he could enjoy it only for 6 months. Atmannoti Samity and Mukti Sangha (later Bengal Volunteers) took upon themselves the responsibility of punishing the collaborator. Shrish Pal was entrusted with the job and he was supported by Ranendranath Ganguli. Ranen kept a watch on thne movements of Nandalal day in and day out and infromed the party. Shrish shot Nandalal at around 7 PM on 9th Nov, near the residence of the later in Serpentine Lane. To be sure that Nandalal had died, Ranendra hot him very hard on his head with his pistol. Thus ended the life of a devious, treacherous snake. Nobody ever got to know who killed Nandalal. Even the revolutionaries did not know, except a few leaders, such was the power of secrecy. Years later, in an independent India, Ranendra wrote about the incident and what really happened. He was well supported by the leaders who were alive. Thus the history got to know who killed Nandalal. One outcome of this incident was that the collaborators were terrified. Nandalal's death was followed by that of Shamsul Alam, Ashutosh Biswas and several other collaborators. British Government was in deep trouble as they could not protect their assets - the Mir Jafars and Jai Chands and hence whenever they came across the killers and their associates they were extremely harsh with them.
source: Shailesh De, Agnijug, translated from the original Bengali