The state Department of Social Services told the Contra Costa Times on Sunday that one patient who was not supposed to be let outside went missing twice in October before Valley Springs Manor in
The department also alleges the facility failed to hand out medications correctly and conduct proper criminal background checks of employees.
The state suspended Valley Springs' license last week.
Sheriff's officials say the patients were left in deplorable conditions.
Alameda County Sheriff' Sgt. J.D. Nelson says they were being cared for by three unpaid staff members — a caregiver, cook and janitor — when authorities arrived on Saturday.
Authorities have launched an investigation.