Sharma, a 'whistle-blower' credited with several sting operations against alleged corrupt policemen, was shot and injured by bike-borne assailants while taking his dog out for a stroll on the night of April 25 in Vishwas Park area of Dabri in south west Delhi.
Delhi Chief Minister Arvind Kejriwal accompanied by the then Home Minister Satyendra Jain and AAP MLA Somnath Bharti had visited Sharma and assured him of security and fair trial in the case.
Upon interrogation, police also arrested two more accused - a builder Naveen Dagar from Gulab Bagh in Nawada and Arun Kumar from DTC depot in Piragarhi, Yadav said.
The Motorcycle used in attack on Sharma and two sophisticated pistols, including one used in the attack, as well as 24 live cartridges have been recovered from the accused, he said.
The builder, Naveen Dagar, had hatched the conspiracy to kill Sharma and gave a job to the accused contract killers and a close associate of the victim, Arun, paying them Rs 20 lakh, he said.
