The arrested men were identified as Gajanan Teddikar (45), Vikas Mishra (30), Mahesh Bhandarkar (53) and Dilip Mhatre (49).
The cash which they allegedly tried to loot belonged to a sugar factory in Karnataka, said Satara Superintendent of Police Sandeep Patil.
The sugar factory's chairman Girish Sarwad and executive director Sudhir Biradar reached Karad in Satara district on Tuesday looking to hire labourers for cutting sugarcane. They were carrying Rs 4.5 crore with them, said another police officer familiar with the probe.
Their friend and former DySP of Karnataka police Basawraj Choukimath and one Subhash Patil were accompanying them.
They invited the accused Dilip Mhatre to their hotel in Karad as Subhash Patil told them that Mr Mhatre, who is the owner of a finance company, was interested in providing them a loan.
Mr Mhatre, who knew that Mr Sarwad and Mr Biradar were carrying huge amount of cash, allegedly planned to rob them, the officer said. The accused offered to drive the two in his Scorpio to another person, who, he said, can provide them a loan, the officer said.
As Mr Sarwad and Mr Biradar got down, the accused started beating them, the officer said.
However, Mr Choukimath, the retired cop, refused to get down from the Scorpio, in which Rs 4.5 crore were also kept.
The accused got into the Scorpio and drove it -- with the former DySP sitting inside -- towards Ratnagiri.
Others, however, alerted police, and the Scorpio was stopped on the road to Chiplun on Tuesday evening. All the accused were arrested and the cash was recovered.
Further probe is on, the officer said.
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