The Okinawa prefectural government said it halted inoculation at a mass COVID-19 vaccination site Sunday following the discovery of contaminants in another lot of Moderna Inc. vaccine, apart from the lots already suspended from use.

More than 1,500 people were slated to receive jabs at the site in Naha before black and pink substances were found in a vial and three syringes during pre-inoculation inspections Saturday afternoon.

The syringes were filled with vaccine from three different vials, which are also separate from the vial containing the substances, meaning a total of four vials may have been contaminated, the prefectural government said.

These vials fall under the same lot number -- 3005293 -- which is different from three other lot numbers identified by Japan's health ministry Thursday as potentially contaminated doses.

About 880 people received shots under this lot number at the vaccination site. The local government said it has not received any reports of health issues.

The Health, Labor and Welfare 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, the ministry halted the use of around 1.63 million doses of the three lots, which came from the Spanish manufacturer for Moderna, as a precaution.

The contaminant problem came at a time when Japan is struggling to contain a spike in coronavirus infections. Okinawa and 20 other prefectures, out of the total 47, are currently under a COVID-19 state of emergency.

The Okinawa government said it will resume inoculating people at the site on Monday by using unaffected vaccine.

==Kyodo

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