Shyama Prasad Roy’s house in the Lake Market area. A Telegraph picture

A ring, which lawyer Shyama Prasad Roy used to claim was worth more than a crore of rupees, led to his death at the hands of his acquaintances, according to police.

A missionary school-educated young man, the son of a retired sub-inspector and a driver were arrested in connection with the murder on Monday, three days after Roy’s decomposed body was found in his Lake Market flat. The investigators believe that six others — including the mastermind, who has the ring — were behind the murder.

The lawyer’s wife and daughter told the police that he had a diamond ring with a magnifying lens fitted to the metal part. Under the lens, tiny images of Hindu gods could be seen in the diamond, they said.

“Roy didn’t wear the ring and didn’t allow even his wife and daughter to touch it. Recently, he had been planning to sell the ring,” said Jawed Shamim, the deputy commissioner of police (south).

From the lawyer’s phone records, the investigators found that Arindam Ghosh, the sub-inspector’s son, had called him an hour before the killing. Ghosh was working for Sanjay, the Howrah-based mastermind of the gang, and 22-year-old Amlan Dutta. Roy had met the duo three years ago at the race course. Six months ago, Sanjay had offered to buy the ring.

The lawyer, however, recently had an altercation with the two and asked them not to visit him. “The duo sent Ghosh to Roy’s house in the guise of an antique dealer,” said an investigator.

On August 14, Ghosh called Roy, saying he would send a buyer to his flat around 6.30pm. He, along with Sanjay and Dutta, reached Roy’s house in a black Santro. The driver was Ram Mondal, the third man arrested on Monday.

A green Sumo with five hired killers accompanied them. The five and Mondal had entered the flat, added the sleuth.