HYDERABAD: A minor boy died and his sister fell critically sick Sunday evening after the children consumed allegedly toxic fries from a street vendor in Hyderabad, authorities said. According to police, the two siblings ate French fries from a local food-seller in Hyderabad's Chandni area and fell sick. They were rushed to a hospital where the brother passed away. Three eateries were sealed following the tragedy. Police said they had also arrested the managers of the eateries in question. Food samples from the eateries would be collected soon, Abdullah Lak, superintendent of police Cantt area said. According to the children's father, four-year-old Humayyun and his twin sister, Aliza, ate French fries at a place after which their condition deteriorated. The father alleged that there was negligence on the part of the hospital staff, who "didn't wash his son's stomach". The doctors said the children had fallen sick after consuming "something toxic". Inspector General Sindh Police Dr Syed Kaleem Imam directed the deputy inspector-general and senior superintendent of police to launch an investigation into the incident. Sindh Chief Minister Murad Ali Shah also took notice of the incident and sought a report from the city commissioner. He directed the Sindh Food Authority to conduct operations in Hyderabad and instructed for the best possible medical treatment of the deceased child's sister.