Unregistered chit fund

Dear experts please advise. My mother is member of a local area kameti (unregistered chit fund ) from last 5 years and had completed many terms of kameti and also got the prize money on time. Recently, term of her one kameti had completed in july 2015 and she had to receive prize money of 150000 rs from the kameti operator. But this time kameti operator refused to pay prize money to her and other 2 members also. Resulting which the three aggrieved members has raised a fir u/s 406 of ipc . Police has also found the diary of kameti operator which contain records of kameti. At present the kameti operator is in police custody of 15 days. Please advise. 1. How we can get our money , as the kameti operator refuse to have any due. Where the other 2 member have cheque from the operator of money due. But my mother have only the written slip of operator. 2. As it is a unregistered chit fund and the matter of default in payment of members due what legal action can be taken against the operator and whether the members of such unregistered chit fund have any legal liability. Please give kind reply at earliest Regards Sagar 9990855818