FORT WAYNE, Ind. (AP) — Prosecutors have dropped a felony drug charge against a Fort Wayne doctor whose license has been suspended while the state investigates allegations he overprescribed prescription painkillers.

The Allen County Prosecutor’s Office on Tuesday dismissed a preliminary charge of narcotic possession against Dr. Michael Cozzi. It’s not clear why the charge was dropped.

Cozzi was charged March 23, a day after federal agents raided his two homes and office. The Indiana Medical Licensing Board suspended his license for 90 days Thursday while a state investigation continues.

Authorities say Cozzi prescribed controlled substances to 1,700 different people. The prescriptions include 2 million dosage units of Oxycodone and 1.2 million dosage units of hydrocodone.

Cozzi’s attorney, Robert Wright, declined to comment on the dismissal.