The pharmacist jailed for allegedly diluting drugs used to treat chemotherapy patients told investigators he cut the drugs' strength "out of greed," according to a Friday court filing by federal prosecutors.

Federal authorities laid out the alleged confession in advance of a hearing Monday during which a judge is to decide whether pharmacist Robert Courtney should continue to be held without bond.

"The defendant stated that he diluted the strength of the chemotherapy drugs out of greed and in order to make more money," the court papers said.

Courtney, 48, was charged Tuesday with a single federal charge of misbranding and adulteration of a drug. His attorney, Jean Paul Bradshaw, has said Courtney will plead innocent but did not immediately return a call seeking reaction to Friday's filing.

"During this interview the defendant admitted that the allegations in the pending complaint are true," the filing stated.

The federal court papers said Courtney was interviewed Wednesday with his lawyer present, and that he admitted he began cutting drug potency in November 2000 and increased that activity in the period March through May this year.

The FBI said samples it tested from Courtney's Research Medical Tower Pharmacy contained between 39 percent and less than 1 percent of the expensive cancer drugs Gemzar and Taxol.

The news has prompted doctors who used Courtney's chemotherapy mixes to scour their records to find patients who got the treatments.

The drugs were distributed directly to doctors by Courtney's pharmacy in Kansas City, and authorities say there's no reason to worry about Gemzar and Taxol handled by other pharmacies.

A government hot line for people who think they might be affected had logged more than 500 calls by Thursday night.

Suits already filed against Courtney include one by a respiratory therapist who says he bought chemotherapy drugs from the pharmacy and the son of a deceased cancer patient seeking more than $50,000. They sought class-action status for their suit.

The alleged dilution was first noticed by Eli Lilly and Co., which makes Gemzar. Authorities said a sales representative for the company found a discrepancy between the amount of Gemzar the pharmacy ordered and the amount it billed an unidentified Kansas City-area doctor.

Federal authorities claim the dilutions would have saved Courtney hundreds of dollars per dose. For instance, Courtney would have saved about $780 for a single order of Gemzar, which is used to treat pancreatic cancer and some types of lung cancer.

Taxol was first approved in 1992 as a second-line therapy for advanced ovarian or breast cancer. It is also used against AIDS-related Kaposi's sarcoma and lung cancer.