Queso Fresco cheese imported illegally from Mexico and sold in a Latino grocery store in Woodburn, Oregon may be tainted with Listeria, Oregon state officials warned Friday.

Oregon’s Health Authority and Department of Agriculture launched an investigation into the dairy product after an infant in Clackamas County fell ill from the bacteria.  Officials traced the infection to batch of queso fresco, a soft white cheese manufactured in Mexico.

Officials believe the cheese was brought into the country illegally because it was found unlabeled and sold in plastic bags, the spokesman said.