The conditions of the four hospitalized were not known Sunday. Placer County officials referred questions about the incident to the California Department of Social Services, the agency that licenses senior care facilities.
Michael Weston, an official with the agency, said on Saturday the incident was under investigation, but released no additional details Sunday.
Department records show Gold Age Villa was licensed as a residential care facility for the elderly in March 2007, with a capacity of six residents, ages 60 and older.
Prior to this incident the last inspection of the facility was conducted on March 12, 2012, where it was cited for an excessive hot water temperature of 130 degrees. The deficiency was corrected and cleared, Weston said.
Repeated calls to Gold Age Villa by The Associated Press on Sunday were not returned.