Blue Bell Ice Cream is now officially under investigation by the Department of Justice for the listeria outbreak that killed three over the last year.

They are concerned that Blue Bell management knew about the contamination as early as 2013 and willfully shipped tainted products anyway.

CBS News reports a facility in Brenham allowed rainwater to leak from the roof into vats of ice cream. They also said workers notified management about unsanitary conditions that went unheard.

All three facilities found contaminated are producing ice cream again that has found its way back on West Texas shelves.