Cameron's caroling event was held Sunday evening outside The Oaks mall in Thousand Oaks.
Video of the event shows hundreds of people gathered to sing Christmas carols, few of them wearing masks or practicing social distancing.
It is generating backlash in Ventura County, which like most of Southern California is seeing a dangerous post-Thanksgiving surge in cases and hospitalizations linked to COVID-19.
Ventura County has reported nearly 27,000 COVID-19 cases since the start of the pandemic.
But on Monday alone, the county reported 2,651 new cases - a 10% increase in a single day.
The county has reported 199 deaths from the virus and 1,307 people hospitalized since the start of the pandemic.