Loss of all records in fire

Hi ,

Suppose someone lost all the records , vouchers, documents from FY 2006-07 to till the date of fire (date of fire in current year, i.e, FY 14-15) . Scrutiny assessments are under way for some of the previous years. 

Can he tell to the Assessing Officer for lossing of all documents/ data. he doesn't have any data/document related to the previous year even till date of firing.

Whether assessing officer has to accept his contention or he may reject the thing , make the assessment as per his asessment. Whether he can ask for documents/ data / vouchers / supportings, etc, which in fact doesn't exist due to lost in fire.

Is any case law available in favour of asseseee or vice versa.

Thanks

Regards

CA Manoj Mehta