The CBI on Saturday questioned arrested TMC leader Anubrata Mondal over the Rs 1 crore lottery he allegedly won, an official said.

Anubrata, who was arrested by the agency in August in connection with the cattle smuggling case, was questioned by the investigators at a special prison in Asansol, he said.

"We went to the prison to question Mr Anubrata about the lottery he won. We are tallying his responses with the statement given by the lottery ticket seller with whom we spoke on Friday," the CBI officer said.

Anubrata was asked about where and how was the money he won from the lottery was spent, he said.

The investigators suspect that ill-gotten money from cattle smuggling was washed through means involving such lottery draws.

The lottery ticket on which Anubrata won Rs 1 crore earlier this year was allegedly purchased by one of his bodyguards on his behalf, sources said.