The complainant in the case, Rakesh Kumar Singh, had earlier told police the money was being transferred to three different bank accounts and belonged to Gurgaon-based businessman Rahul Ahuja and his partner Rajesh Kalra.
Police sources said the victims were making contradictory statements about the source of the money. Police also suspect the money may have been part of hawala transactions and besides Indian currency, dollars and euros were also being ferried.
The sources claimed Kalra was trying to avoid joining the investigation and alleged that he wanted to pass off the money as being clean.
The complainants had claimed that the money was part of a transaction related to a property deal, but were later unable to give details of the deal and the source of money.
Police also suspect the money was not being transferred to bank accounts but to be deposited in the lockers of three banks.
It was found that the Rs 8 crore was to be transferred to lockers and not bank accounts. It seems Rakesh was instructed to not divulge all details about the cash being transported, a source claimed, adding that the income-tax department is likely to join the investigation.
Police sources also said that three of Kalras associates, who were supposed to accompany the Honda City to the banks in another car, reportedly took a different route.
It is now suspected that one of the occupants of the other car, whose uncle is lodged in a jail in Jhajjar on charges of robbery and murder, conspired against Kalra and staged the robbery.
Police suspect the uncle runs a racket from jail and planned this robbery. A police team has been sent to Jhajjar.
Sources also said they are probing a betting angle in the case as they suspect Kalra was in touch with Sandeep Chawla, a London-based bookie who is also accused in the match-fixing scandal.
There is a possibility that the unaccounted money was generated from a betting racket, possibly from the ongoing New Zealand-India series or for the upcoming IPL matches. This angle is also being probed, a police source said.
Police are also probing suspected links between Chandresh Jain alias Jupiter, a key suspect in the IPL alleged spot-fixing case, and Kalra and a team has been sent to Jaipur, where Jain lives.
Sources said Kalra told the police he was not aware of how much money his employees were transporting as large amounts are regularly ferried to banks.