A report on questionable insurance claim activity last year showed suspicious claims have been on the rise since 2008. The National Insurance Crime Bureau reported that in 2010, 91,797 claims were referred to the bureau by its member insurance companies for further investigation based on indications of possible fraud. That figure was up 8.7 percent from 2009 and 24 percent since 2008, said the report. Auto-related claims were reported the most, with cases of auto glass fraud climbing 450 percent from 2009 and reports of inflated towing and storage bills rising 116 percent.