The Centers for Disease Control and Prevention is warning consumers not to eat romaine lettuce as officials investigate a new outbreak of E. coli.

Tainted irrigation water appears to be the source of a national food poisoning outbreak linked to romaine lettuce, health officials said Thursday. 

The Centers for Disease Control and Prevention is expanding its warning to consumers to avoid all types of romaine lettuce from the Yuma, Arizona growing region due to a growing E. coli outbreak that has sickened people in 16 states. 

Health officials are warning of contaminated lettuce that could be the cause of the current E. coli outbreak that has now sickened people in 11 states.