The police on Wednesday found the Skoda car which was used by the killers and said they had quizzed around 12 people in connection with the case which was helping them zero in on the suspects.
Police also questioned Bhardwaj's family and guards at his farmhouse on the Delhi-Gurgaon border.
Meanwhile, the autopsy of Bhardwaj's body was conducted on Tuesday and two bullets were found lodged.
The police on Tuesday had released footage from security cameras of two men who shot dead the BSP leader.
The 27-second clip showed a grey Skoda car drive up to the farmhouse gate and out of which two men emerged. One was brandishing a revolver, apparently to threaten the security guard, and opened the gate.
The gun-toting man turned briefly and his face was visible for a few seconds before the two follow the car out of the farmhouse as the camera clock read 9:14 in the morning.
Bhardwaj, 62, who had also contested polls earlier, was shot dead inside his farmhouse on Tuesday morning by the two assailants in south Delhi who then fled the scene.
The slain businessman and politician was one of the richest contestants of elections in 2009 on a BSP party ticket, reports said. He, however, did not win the polls.
Bhardwaj, who had contested from the West Delhi constituency unsuccessfully, had real estate business, hotels and was in the education sector too.
--IBNS (Posted on 27-03-2013)