A mother-son insurance fraud team who operated a ring of medical clinics that routinely over-billed insurance companies was indicted yesterday along with 13 others who allegedly assisted their scam, Robert Morgenthau, the Manhattan district attorney, announced yesterday.

Over the past decade, the clinics had billed more than 60 insurers for millions of dollars in claims.

Two separate investigations led detectives directly to the mother-son duo, Isabella Pustilnik, 57, and Abraham Pustilnik, 34, as well as Mr. Pustilnik’s wife, Inna Pustilnik, 32, who owned and operated several medical clinics and a billing agency in Manhattan and Brooklyn, police said. Concealing the true ownership of the clinics behind licensed professionals, the Pustilniks allegedly billed insurance companies for medically unnecessary testing and procedures that were never performed on patients, and also inflated the amount of time doctors spent treating their patients, Mr. Morgenthau said.

A total of 15 individuals, including a dentist, chiropractor, and psychologist, were charged with insurance fraud, grand larceny, attempted grand larceny, and scheme to defraud. All were released on bail yesterday afternoon.

Police began their investigation nearly a year ago when they were approached by an elderly couple who had sought treatment at the Omni Medical Center at Brooklyn, one of the Pustilnik owned clinics. On the advice of their lawyer, the couple went to the clinic following a minor car accident, but immediately felt pressured to sign for unnecessary treatments, said Angelo Carbone, a lieutenant with the Fraudulent Accident Investigation Squad.

Insurance fraud investigators who posed as accident victims had similar experiences at the clinic, Mr. Morgenthau said.

One undercover officer was given only a few hot packs and electrical therapy for his purported injuries, but his insurance company was billed for more treatment than he had received. According to investigators, Omni staff had allegedly directed the officer to back-date sign-in sheets for times when he had never had appointments and to sign for treatments he did not receive, including acupuncture, chiropractic adjustments, and counseling.

Patients were often under the impression that by going along with the scam, “they would get a big bodily injury suit at the end,” Mr. Carbone said.

Lawyers reprsenting the Pustilniks did not return phone calls for comment.