Two children died from E. coli in southern Utah in recent weeks, the Southwest Utah Public Health Department confirmed Monday, as reported by KSL.

Four other incidents of E. coli have also been reported in the area of the border towns of Hildale and Colorado City, Arizona, said Southwest Utah Public Health Department spokesman David Heaton.

The incidents are limited to that area, he said.

The cause for the outbreak is still being investigated, but health officials believe it can likely be traced to contamination from food or animals. Heaton says investigators don’t think the town’s water supply is the cause.

Before Monday, Heaton had refused to confirm the deaths. He declined Monday to release the names, ages or genders of the two children who died. He said the four non-fatal cases are a combination of children and adults but said he didn’t have the exact breakdown. Some of them are still being treated, though none of their conditions were released.

Multiple people who identified themselves as relatives of 6-year-old Gabriella Addison Fullerton indicated on Facebook that she was one of the victims who died. On a GoFundMe webpage* published Friday seeking donations for funeral costs, loved ones called Gabrielle “our little angel” who “has passed on to a better place.”

“Her family is completely devastated at losing such a precious and loving child. She was taken at the tender age of 6. … Hold your babies close every chance you get,” the page states.

Both Hildale and Colorado City are well-known for being largely polygamous communities, with many residents being members of the Fundamentalist Church of Latter-Day Saints.