The Okinawa prefectural government said Saturday that it has found foreign matter in an unused vial of Moderna Inc.'s COVID-19 vaccine not belonging to batches already suspended from use following the discovery of contaminants.

Japan's health ministry said Thursday that foreign substances have been confirmed in 39 unused vials at eight vaccination sites in five prefectures -- Ibaraki, Saitama, Tokyo, Gifu and Aichi.

The same day, it halted the use of around 1.63 million doses, or three lots, which came from the same production line of a Spanish factory, as a precaution.

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