California’s largest nursing home owner is facing a new round of government scrutiny as the FBI served search warrants last week at his Riverside facility, and two more of his former top administrators have been charged criminally by the state attorney general’s office.

FBI spokeswoman Laura Eimiller confirmed Saturday that FBI agents executed search warrants “seeking evidence in relation to alleged criminal activity” at a 99-bed facility in Riverside owned by nursing home magnate Shlomo Rechnitz.

Eimiller said she could not comment on the exact nature of the federal probe because the affidavit in support of the warrants is under seal. However, the FBI spokeswoman said it was her understanding that agents took documents, and that “patients were not removed or even disturbed” during Thursday’s raid at the Alta Vista Healthcare & Wellness Centre.

The latest investigations shine the spotlight again on Rechnitz, a 44-year-old Los Angeles entrepreneur whose facilities have been the focus of multiple local, state and federal probes, along with stepped-up scrutiny by health officials.

His stable of nursing homes in California has expanded rapidly in the last decade, giving him control of about 1 in every 14 skilled nursing beds in the state, according to a Bee investigation. With an estimated 80 homes under his control, Rechnitz has widespread influence on the quality of care being delivered in skilled nursing facilities, which serve some of the state’s most vulnerable residents.

The Bee found that homes he owned for all of last year were tagged with nearly triple as many serious deficiencies per 1,000 beds as the statewide average in 2014, according to the latest figures from the federal Centers for Medicare and Medicaid Services.

Sallie Hofmeister, a spokeswoman for Rechnitz and his facilities, said Saturday in an email to The Bee: “We are not aware of any basis for the (FBI) investigation, but are cooperating fully with authorities. We cannot comment on the specifics of the discussions with the authorities, but at this time we have no reason to believe the investigation has anything to do with patient care. Alta Vista is proud of the care and treatment it provides to its patients.”

Besides last week’s FBI raid, several Rechnitz employees are facing their own legal challenges.

The former administrator and former top nurse at one of his Orange County nursing homes were charged criminally in August in connection with the alleged abuse last year of two residents – one of two criminal cases filed by the California attorney general in August against employees at facilities owned by Rechnitz.

Joseph Munoz III and Milagros Victoria Soqueno have been charged with four misdemeanor counts each of inflicting injury on an elder adult and failing to report elder abuse. Munoz had been the administrator of the 80-bed Mesa Verde Post Acute Care Center in Costa Mesa, and Soqueno was the nurse in charge at the time of the 2014 incidents, according to the Attorney General’s Office.

Soqueno’s and Munoz’s charges stemmed from the discovery last year by a Department of Public Health inspector that a resident at the facility had been inappropriately touching other patients, and staff knew about it but failed to immediately report the incidents or protect residents from further harm, said AG’s spokeswoman Kristin Ford. After prompting from health officials, the facility eventually filed the mandated abuse reports, she said.

Arraignment is set for Dec. 10 in Orange County, and the case is being handled by the AG’s Bureau of Medi-Cal Fraud and Elder Abuse.

Hofmeister, spokeswoman for Rechnitz and his facilities, said that “no employees were arrested at Mesa Verde Post Acute Care Center.”

“The facility investigated the allegations and the employees are no longer with Mesa Verde,” she said in Saturday’s email. “The facility has cooperated with authorities and has not been cited for the incident.”

Also in August, Attorney General Kamala Harris announced that her office had filed involuntary manslaughter charges against Verdugo Valley Skilled Nursing & Wellness Centre LLC, a 138-bed facility owned by Rechnitz in suburban Montrose, near Glendale. In that criminal case, the AG’s Bureau of Medi-Cal Fraud and Elder Abuse brought felony charges against two registered nurses at the facility, accusing them of dependent-adult abuse in connection with the death of a burn victim, who allegedly was neglected. The preliminary hearing in that case is set for Dec 8.