Weight loss doctor Gautam Gupta is wanted by the Federal Bureau of Investigation for allegedly sending fraudulent claims to health insurance agencies in his home state of Illinois.

The FBI in partnership with the Illinois Healthcare and Human Services Department have been investigating Gupta, who ran six weight loss clinics in Illinois and Southern Wisconsin, since January of 2010. Private health insurance companies and the state funded Medicaid program may have paid $25 million in fraudulent medical claims to Gupta, according to the source.

Dr. Gupta’s website claims to offer medical weight loss therapy and FDA-approved drugs that help patients on the road to permanent weight loss. Patients who visited Gupta’s facilities thought they were being attended by nurses when they underwent a number of tests involved in the process, however, none of the clinics employed any actual nurses, according to Medical News Today.

Furthermore, former employees claim that he urged them to doctor patient charts so more tests could be performed. The doctor, whose whereabouts are unknown, is also being charged with mail fraud, conspiracy and medical fraud.