The New York Times reports that a second company in California has been implicated in the E. coli outbreak linked to spinach, the Food and Drug Administration said late Sunday, and the number of identified victims is still rising.

The newly identified company, River Ranch Fresh Foods, obtained salad that included spinach from the first company implicated, Natural Selection Foods of San Juan Bautista, Calif.

The spinach that passed through River Ranch was sold under the brand names Farmers Market, Hy-Vee, and Fresh and Easy. The investigation is proceeding in what amounts to a rearview mirror, with state and local health officials receiving reports of illness, asking people what they ate and searching for the source. To identify the new company, officials examined Natural Selection’s records and found it had supplied River Ranch.

The number of reported cases of E. coli infection rose by seven on Sunday, to 109, but officials said that the real number was probably higher and that reporting was probably delayed because some health departments were not staffed on weekends. They also said they expected the number of states in which cases had been reported, 19 on Sunday, to rise.