WASHINGTON, D.C. ? An outbreak of E. coli in eight states has left at least one person dead and 50 others sick, federal health officials said Thursday in warning consumers nationwide not to eat bagged fresh spinach.

The death occurred in Wisconsin, where 20 people were made ill, state officials said. The outbreak has sickened others – eight of them seriously – in Connecticut, Idaho, Indiana, Michigan, New Mexico, Oregon and Utah, according to federal health officials.

In California, state health officials were investigating a possible case that could be linked to the outbreak and warned consumers not to eat the produce.

The Centers for Disease Control and Prevention and Wisconsin health officials alerted the FDA about the outbreak Wednesday. Preliminary analysis suggests the same bug is responsible for the outbreak in all eight states.

The warning applied to consumers nationwide because of uncertainty about the origin of the tainted spinach and how widely it was distributed.

E. coli causes diarrhea, often with bloody stools.