RIVERHEAD, N.Y. — A Long Island doctor who wrote hundreds of illegal prescriptions has been sentenced to three years in prison.

Michael Chait (Ch-ATE) pleaded guilty in April to drug possession, conspiracy and grand larceny charges. New York Attorney General Andrew Cuomo has called it a case of physician-assisted drug dealing.

Prosecutors contend that in early 2007, Chait saw up to 50 patients a day in his Hamptons office. Many were Medicaid recipients from New York City who went to his office to pay cash for the phony prescriptions.

The buyers then would return to the Bronx or Manhattan, where they would have their prescriptions filled and sell them on the black market. The drugs included the painkillers OxyContin and Dilaudid.