Two patients died after receiving Moderna COVID-19 vaccination doses from the same production line that had been halted due to contamination.

Two men in their 30s died lately after receiving their second Moderna doses, according to Japan’s health ministry. On Thursday, each received a jab from one of three production lots that had been banned.

The cause of the deaths, however, is still being probed.

Following allegations of contamination in some vials, Japan halted the use of 1.63 million Moderna doses distributed to 863 immunisation centres around the country.

On Thursday, Spain’s ROVI pharmaceutical firm, which manufactures Moderna’s COVID-19 vaccine, launched an investigation to establish how vials of the vaccine supplied to Japan became contaminated with foreign particles.

Moderna, a US vaccine manufacturer, is apparently launching a parallel inquiry.

According to the NHK broadcaster in Japan, the contaminants were magnetic and seemed to be metallic particles. There have been no reported safety concerns associated with the three lots.

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