Since you have already notified the bank about the cheques being stolen and instructed them to stop payment in the event of it being presented at a later date nd also as your partnership firm is not functioning and is in  a dormant stage,, these things are in your advantage to defend yor interests.

However if you ant to take further safety measures, you can issue a public notice in two local newspapers, one in vernacular language and another in a English language, besides you may even lodge a criminal complaint against the person who is alleged to have stolen the cheques.

These steps would perfectly save you from any liabilities including a cheque bounce cae if at all he is playing a mischief at a later stage with the help of the blank cheque.

For drafting the notice and other issues you may approach a local advocate or an advocate of this forum too on the terms of the advocate.

1. The very first step you should have taken, when the cheques were stolen, to lodge an FIR or make a Police Complaint.  That minimizes your risk, as that proves if the same cheque is issued to someone and it bounces, the liability mounts on the person who made the signture. 
2. Now you can make amendments in the Partnership and pass a resolution to close the dormant bank account. Closing of the bank account cancells all the accessories provided to you along with it.
3. Thereafter, you need to choose any 2 (Hindi and English) newspapers which are local newsaper, thereby mentioning that you are taking voluntary retirement from the partnership and I shall not be held liable for anything that happens n the future course. 

You should file police complaint about cheques stolen by partner 

2) you can issue public notice about your retirement from firm and stolen cheques 

3) it should be published in one English and Hindi newspaper in your city 

4) contact a local lawyer 

You may also lodge a police complaint. If you any assistance regarding filing online, you may contact me through this platform or search me on google.

- If you have made stop payment without giving compliant to the police for the missing of said cheque , then it will have no legal impact upon the case, if that cheque will be misused .

- Signed blank cheques are just like loaded revolver , if any other person even by mistake fired from the same, then the owner of that revolver will be held responsible

- However in case of cheque , the misuser will have to show the liability that why it was issued to him .

- Hence even now you can give a compliant as information to the police after narrating that only now you came to know that some cheques are missing from the cheque book , and if misused then you will not be accountable for the payment , and further forward the said complaint copy to the bank accordingly. 

- Further, for your retirement and responsibility , you can advertise the same in local circulated papers. 

- You can contact me , if further suggestion needed. 

Dear sir/ma'am,

1. You can choose a regional vernacular newspaper and a national newspaper(Times of India, Dainik Bhaskar, etc.)

2. Regarding the notice of stollen cheques- Notice is hereby given that the C forms issued by (company's name) have been misplaced and cannot be traced. 

3. Regarding the notice of retirement- Notice is hereby given to all affiliates of the (Company Name) that I am retiring from the position at ...(company's name)... also a notice should be advertised in the Official Gazette and Registrar of firms

Thank you