Federal authorities have arrested a doctor and nurse accused of operating a “pill mill” — a pain management clinic that accepted only cash and doled out prescription painkillers to patients without conducting medical exams — in New Orleans East.

Dr. Barbara A. Bruce and Theresa “Tammy” Schlosser, who worked at the Axcess Medical Clinic, were taken into custody this month on allegations they conspired to dispense controlled dangerous substances. Federal court papers indicate that three fatal overdoses have been “associated with Bruce.”

A criminal complaint filed in U.S. District Court identified the owner of the clinic as Kenny Knight, a longtime adviser to former Ku Klux Klan leader David Duke.

The U.S. Drug Enforcement Administration has been investigating the clinic since 2010, believing the business was prescribing drugs “without a legitimate medical purpose,” according to the 18-page complaint.

Knight, who did not return calls seeking comment Wednesday, has not been charged in the case. The criminal complaint said he recently had a “dispute” with Bruce and reported her use of “pre-signed prescriptions” to the State Board of Medical Examiners, which investigates doctors.

The DEA conducted several months of surveillance outside the New Orleans East clinic and, beginning in December, sent undercover informants into the office wearing wires.

The investigation found that Bruce drew a steady stream of patients, including addicts who traveled for hours to get to the clinic and were allowed to suggest medications of their choice. Staff members conducted sham therapy sessions, according to the complaint, and in some instances, falsified patient files to lend a veneer of legitimacy to the clinic.

On some occasions, the complaint says, the clinic handed out prescriptions to patients who had not even met with Bruce. During one visit in February, a patient cooperating with the DEA received a 29-day prescription from Schlosser — who worked as an office manager and triage nurse at the clinic — for four different drugs, including oxycodone and Xanax. Bruce’s vehicle appeared to be parked at the clinic, but she did not evaluate the patient’s complaints of pain, the complaint says.

Bruce, who often referred to drugs by their street names, is also accused of helping at least one patient subvert the clinic’s drug screening rules by signing off on altered records that made it appear the patient had not failed a urine test.

“Between you and me, I could care less how much weed you smoke as long as you can come in here and you can pass a urine drug screen,” Bruce told the patient, according to the complaint, written by DEA agent Cecil McCaw.

Agents spotted Bruce leaving the office one day in March with “several shoulder bags and a folded manila folder, which agents suspected was money” from the business. The agents followed the doctor to a Chase Bank branch and later to her residence on St. Philip Street. The complaint says agents suspected Bruce had been taking “financial documents, patient documents and other related” materials from the clinic’s office to her home.

The DEA learned in late April that Knight was “looking for a new doctor” following an apparent falling-out with Bruce, the criminal complaint says. Knight told the State Board of Medical Examiners “that there had been four overdoses associated with Bruce — three deaths and one that resulted in the person being on life support,” the complaint says.

Bruce allegedly took the clinic’s appointment book with her when she left and opened a new office on Front Street in Slidell. Agents surveilling her new office determined that several of the vehicles outside it were registered to patients who earlier had been issued prescriptions at the Axcess Medical Clinic.

While Knight has not been charged, court documents make clear that the DEA has taken a keen interest in his actions. Earlier this month, agents surveilling the New Orleans East clinic watched as he carried a blue file or folder from the office to his vehicle and drove away. They followed him “to an address known to be Schlosser’s apartment” and watched him carrying some clothing up to the residence, according to the complaint.

Well known as a chief aide to Duke, Knight had remained largely out of the public eye for years. That changed about six months ago, when liberal blogger Lamar White uncovered a report that U.S. House Majority Whip Steve Scalise — then a state representative — had addressed a 2002 Metairie convention of Knight’s European-American Unity and Rights Organization, a white nationalist group. Scalise said speaking to the group was “a mistake I regret” and condemned its mission, heading off a controversy that churned for several days.

According to the DEA, Knight moved the pain clinic to Picayune, Mississippi, for a time before returning the business to New Orleans East. The clinic drew the attention of law enforcement in Mississippi, as well, and local police in 2010 searched the business and arrested two Ponchatoula men on counts of illegal drug possession.

Knight complained to The Picayune Item newspaper at the time that the authorities’ search of patient vehicles had been illegal.

“I’m planning on taking this to the FBI, you can quote me on that,” he told the newspaper. “This is Mississippi (circa) 1950.”

Follow Jim Mustian on Twitter, @JimMustian.