In the study, all cases occurred within 6-31 h with a median incubation period of 15 h. Such incubation period is seen in food poisonings due to Salmonella spp, Clostridia spp and some cases of B.cereus. Clostridia spp food poisoning commonly occurs following consumption of food which was prepared 24 h or more before consumption and present with diarrhoea but no fever. Diarrhoeal form of B.cereus has a minimum incubation period of 12 h and do not have fever. Hence Clostridia and B.cereus are unlikely cause of the present outbreak