Attorney General Andrew Cuomo has subpoenaed more than 50 home health care agencies as part of an investigation into industry-wide wrongdoing ranging from unqualified caregivers to Medicaid fraud.

“The evidence we’ve obtained to date suggests endemic, persistent fraud and malfeasance at all levels of the home health care industry,” Mr. Cuomo said in a statement yesterday.

The letters request that agencies disclose information about the aides they employ, including verification of their qualifications and hours billed.

A spokesman for the attorney general’s office said as many as 100 defendants could be implicated in schemes that include deceptive billing practices. The investigation is expected to recover up to $100 million and could result in dozens of arrests, the spokesman said.

The subpoenas are part of a wide-scale investigation of the home health care industry that has been going on for several years. The investigation, called Operation: Home Alone, was first reported in yesterday’s New York Post.

In the past six months, the attorney general’s Medicaid Fraud Control Unit has implicated several home health care aides in fraudulent schemes. Most recently, a Suffolk County home care nurse was sentenced to 60 days in jail for falsely billing Medicaid for $150,000 in services.

Reacting to news of the attorney general’s investigation yesterday, officials at several health care organizations said they have been working with the state’s Department of Health to establish regulations for validating the certification of home health care employees.

Some expressed concern that the entire industry was being painted as fraudulent. “I think we’re concerned right now about ensuring that there is a clear difference between those who have done wrong, and those who are following the rules,” the executive vice president of the New York State Association of Health Care Providers, Christy Johnston, said.