Packaged salads produced at an Ohio Dole Fresh Vegetables Inc. facility have been linked to a multistate outbreak of Listeria monocytogenes infections, including one death in Michigan, according to the CDC.

In all, 12 people in six states—Indiana, Massachusetts, Michigan, New Jersey, New York and Pennsylvania—have been infected starting in July 2015. All of those infected were hospitalized with many reporting eating packaged salad in the days before becoming ill.

Though the investigation is ongoing, the CDC says the source of the outbreak points toward packaged salads produced by Dole under the names Dole, Fresh Selections, Simple Truth, Marketside, The Little Salad Bar and President’s Choice. CDC linked the outbreak to Dole after the Ohio Department of Agriculture tested salad manufactured at the Dole Springfield, OH plant that was purchased from a retail location. The results of this test revealed listeria that was “highly related genetically” to the strain of the bacteria that made people sick.

As a result of the outbreak, Dole has temporarily suspended all operations at the Springfield plant and is recalling all Dole branded and private label packaged salads processed at the facility from more than 20 states and three provinces in Canada. No other Dole products or facilities have been linked to the outbreak.