Four operators of an ambulance company that serves Orange County were arrested Oct. 4 under a federal indictment alleging more than $49 million in bogus Medicare charges, one of the largest such schemes in California history.

The arrest of the owner-operators of Alpha Ambulance Inc. of Los Angeles is part of a national crackdown in which 91 defendants in seven cities are linked to a total of about $430 million in false Medicare billings.

A spokeswoman for the Orange County Health Care Agency, which licenses ambulances, said emergency medical services officials are investigating Alpha Ambulance’s operations in the county with heightened concern after the indictment.

Federal agents also arrested an Anaheim physician, Dr. Sri J. “Dr. J” Wijegunaratne, also known as Wijegoonaratna. He is accused of writing medically unnecessary prescriptions for power wheelchairs in return for kickbacks that generated $1.5 million in false Medicare billings for a San Bernardino firm. Wijegunaratne couldn’t be reached for comment.

Alpha Ambulance is alleged to have begun fraudulent billings soon after the firm was founded in 2007. The eight-count indictment also alleges a conspiracy to cover up false billings last spring as U.S. Health and Human Services officials began an audit.

An official at Alpha Ambulance’s office said in a telephone interview that no one was available to comment. All four defendants went before a magistrate in U.S. District Court in Los Angeles.

In a press conference in Washington, D.C., U.S. Attorney General Eric Holder cited the $49 million in the Alpha Ambulance case as one of the major achievements of the nationwide Medicare Fraud Strike Force sweep.

“Such activities not only siphon precious taxpayer resources, drive up health care costs and jeopardize the strength of the Medicare program, they also disproportionately victimize the most vulnerable members of society,” said Holder.

After a federal strike force raid in June in which records were seized, Alpha Ambulance was identified as one of the suspicious companies that had expanded operations in recent years into Orange County as Los Angeles County tightened ambulance regulations.

The 16-page indictment issued on Sept. 21 in Los Angeles but kept secret until Oct. 4 lists Alpha Ambulance defendants arrested as:

Alex Kapri, also known as Kapriyelov, 55, of Hollywood Hills, the president-chief executive ; Aleksey “Russ” Muratov, 51, of Burbank, the chief financial officer; and employees Wesley Kingsbury, 33, of Bloomington, and Danielle Medina, 35, of Corona.

While officials with the U.S. Department of Health and Human Services allege that Alpha Ambulance submitted $49.3 million in false Medicare claims, the indictment states only $13.3 million was paid to the company.

Kristen A. Williams, an assistant U.S. attorney in Los Angeles who coordinates major fraud probes for the Medicare Strike Force, said agents are going through the voluminous claims to sort out their origins from various counties.

A total of 18 individuals including two other physicians were arrested in at least four Southern California counties.

The indictment alleges that Alpha operators knowingly provided medically unnecessary ambulance services to Medicare beneficiaries for trips to hospitals, diagnostic facilities or clinics, such as dialysis providers. Then Alpha Ambulance officials altered records for the ambulance runs to conceal the fraudulent nature of the claims, the indictment asserts.

After being notified last spring that a federal audit was under way, the officials conspired to cover up $100,000 in fraudulent billings made on behalf of 60 Medicare beneficiaries during a one-year period, according to the indictment.