Clinton House Nursing Home in St Austell, Cornwall, which is run by the Morleigh Group, has closed its doors and three more of its sites are being investigated according to a BBC report.
The home, which cares for 30 people, closed following serious concerns about the safety of residents.
It was given extra nursing staff to protect the health of residents after fears were raised last month.
The BBC reported that Cornwall Council said the “unusual and serious” decision to move residents had been taken due to safeguarding issues.
Morleigh operates six homes in Corwnall and St Theresa’s Nursing Home in Callington, Elmsleigh Nursing Home in Par and Collamere in Lostwithiel are all being investigated.
The CQC, local council, NHS Kernow CCG, Devon and Cornwall Police and NHS England have formed an action group following concerns raised last month.
The police force told the BBC that no arrests had been made, while the CQC said the findings of its recent inspections of four Morleigh premises would be reported “in due course”.