Agarwal was shot dead by two bike-borne shooters when he was parking his car at his house in Gangapur on June 9 over property dispute, IG Police (Jaipur Rural) D C Jain said.
Six persons - Yogesh Yogi, Shaukin alias Shivkishan, Chintu Chinmay, Shivcharan Meena, Monu Aga, Rajendra alias Chirda - were arrested in this murder case, Jain said, adding, all of them have criminal records.
During initial interrogation, the main accused Yogi told police that he had a link with a jail inmate named Kamal Meena who is lodged at Alwar Jail.
Kamal then contacted Yogi who then planned the murder, he said.
Police are interrogating Kamal Meena and another inmate in the prison in connection with this case, he said.