Toby Carvery is being sued by almost 200 diners after they fell ill with a severe vomiting bug at a restaurant in Exeter, Devon.
Solicitors Irwin Mitchell is representing 193 people who were struck down by the norovirus before Easter.
Exeter Express and Echo reports that the Toby Carvery at the Exeter Arms, Middlemoor, was cleaned overnight after they were made aware of the outbreak but continued to welcome diners over the Easter holidays.
Tonia Kingsley, an expert public health lawyer at Irwin Mitchell, said: "It is very alarming to see this number of people affected by an illness outbreak of this nature in the UK."
She added: "Through our work we know just how debilitating gastric illness can be and the significant impact it can have on the day-to-day lives of victims, as well as the long term effects which some can face.
"It is vital this issue is not underestimated and, as part of our work, we'd be keen to hear from anyone else affected by the problems."
According to the Daily Mail, a Toby Carvery spokesman said staff steam cleaned the restaurant and were told by Environmental Health that they could continue trading.
"We would like to reassure our guests that hygiene standards are of primary importance to our business and we have taken all the necessary safety precautions before reopening."
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