A second case of E. coli was reported in Connecticut on today, as federal officials worked to find the source of the 10-state outbreak linked to bagged spinach.

A Wisconsin resident died and dozens of others have been sickened. The Food and Drug Administration warned people not to eat bagged spinach and said washing it wouldn’t solve the problem because the bacteria are too tightly attached. Supermarkets around the country began pulling packaged spinach from store shelves.