The Mumbai crime branch said it had telephone intercepts that could help nail Gurunath Meiyappan, the team principal of Chennai Super Kings (CSK).
A highly-placed crime branch officer said the agency would be able to prove Meiyappan's involvement in betting from the conversations he has had with Virendra Dara Singh alias Vindoo and others.
Nearly 250 calls that Vindoo made, mostly to Meiyappan, are under scrutiny, sources said.
“The two spoke around five times on days of the T20 league matches. And we have several of those intercepts,” an officer privy to the investigation said.
Himanshu Roy, joint commissioner of police, crime, said they had enough evidence to file a charge sheet against Meiyappan in court.
The crime branch is now waiting to get the results from the forensic science laboratory, which has been tasked to extract the content from Meiyappan's laptop and mobile phones.
Also, the crime branch is probing if Meiyappan had placed bets in the earlier seasons of the T20 tournament.
Being 'closely associated' with the franchise, he routed his bets through other bookies such as Vindoo, officials said.
Meiyappan, who according to sources knows many cricketers, allegedly placed bets on other franchises apart from CSK.
He used four phones to place bets and to pass on team planning and strategies to Vindoo, said officials.