The Federal Bureau of Investigation (FBI) is investigating a nursing home in Beaver County, Pa., where more than 300 residents and staff were infected with COVID-19 and at least 73 residents and a housekeeper died.

TribLive, the website of the Pittsburgh Tribune-Review, first reported the news.

Investigators with the agency on Thursday served warrants at Brighton Rehabilitation and Wellness Center, U.S. Attorney Scott Brady confirmed to the publication, in addition to executing court-authorized warrants at Mount Lebanon Rehabilitation and Wellness Center.

Sam Halper of Pittsburgh and Ephram Lahasky of New York, two of Brighton’s owners, have shares of the Mount Lebanon nursing home, according to federal records cited by TribLive.

The management of the facilities could not be reached for comment by TribLive.

The warrants were served by special agents with the FBI, in collaboration with the Health and Human Services division of the Office of Inspector General, the criminal investigation unit at the Internal Revenue Service and the Pennsylvania Attorney General’s Office, according to a statement from Brady cited by TribLive.

The Centers for Medicare & Medicaid Services (CMS) also investigated Brighton Rehab and sent inspectors to the property in May, but the results of that probe have not been made public.

Pennsylvania attorney general Josh Shapiro launched a criminal investigation into Brighton Rehab in August after a TribLive investigation into the facility.

In May, Department of Health and Human Services secretary Alex Azar had promised an investigation into the property.

The move marks the most recent federal effort to investigate nursing homes after the Department of Justice last week requested information from four state governors about their policies regarding admissions during the peak of the COVID-19 pandemic, among other data points.

Critics of the DOJ investigation have described it as partisan; all four governors, including New York’s Andrew Cuomo, are Democrats, and the DOJ operates under the auspices of the Republican Trump administration.