The Ibaraki Prefectural Board of Education said Tuesday that 379 students at 61 schools in the prefecture felt sick after drinking milk served during lunchtime at school the previous day.
Two of them went to the hospital, but all of them are recovering, board officials said.
According to the officials, more than 3,700 students and teachers at 60 elementary and junior high schools and a special needs education school in eight cities and towns in the prefecture, including Mito and Kitaibaraki, said the milk served at school that day tasted watery or smelled like an antiseptic solution.
The milk, served in 200-ml cartons, was supplied to 298 schools in 16 municipalities in the prefecture by Ibaraku Co., which has a milk plant in Mito. The Mito public health center had begun inspecting the plant Monday.
The company suspended shipping of the product and apologized, saying it will conduct strict hygiene management.