Japanese police on Monday arrested a man who posed as a doctor to earn cash, examining 2,300 people with little more than a few hours of self-study to back it up, police and media said.

Miyabi Kuroki, 43, had no experience of medical school and passed himself off as a qualified doctor after finding the identity of a legitimate physician on the Internet, Jiji Press reported.

He was dispatched by an employment agency to a Tokyo hospital where he conducted medical interviews, examined electrocardiograms and explained check-up results to more than 2,300 people, local media said.

He was undone when a medical exam study school where he had "taught" became suspicious and contacted the hospital.

Police in Tokyo said Monday they had arrested Kuroki on suspicion of forging a medical licence in 2009 and earning 2.62 million yen ($34,000) by illegally working part time as a doctor at a hospital in Tokyo in 2010 and 2011.