Residents of the city of Ruichang suffered symptoms of diarrhea, vomiting and fever after taking part in the Thursday evening lobster feast, China's state-run news agency Xinhua reported.
Doctors who treated people at Renmin hospital said they suspected E. coli as a possible cause of the illnesses.
More than 4,000 people reportedly attended the feast, part of the Ruichang's government-sponsored lobster festival.
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