The NHS fraud squad is investigating GPs in England amid suspicions they are claiming for non-existent patients.
Doctors get £150 a year for each patient on their list, but records show there were 3.6 million more patients in the system last year than there were people in England.
The discrepancy prompted NHS England to employ a company to start chasing up these so-called ghost patients.
The NHS Counter Fraud Authority is now launching its own investigation.
Doctors’ leaders have always insisted the issue of ghost patients most often has an innocent explanation, such as instances where patients have died or moved without the knowledge of their GP.
It is understood the list-cleaning exercise, being carried out for NHS England by the business services company Capita has started to see a