Japan has suspended the use of 1.63 million doses of the Moderna vaccine because of its combination with ‘unknown substances’.
The health ministry said "foreign substances" were found in several doses of approximately 560,000 bottles of the vaccine.
The pharmaceutical company Takeda, which sells and distributes the vaccine in Japan, said Moderna was holding three shipments "as a precaution".
It said the issue in the manufacturing sector in Spain was the reason for the situation but did not elaborate.
"So far, no safety or effectiveness issues have been identified," Moderna said, adding that it would work with management and Takeda to investigate the matter further.
There is no explanation for what "foreign objects" are, but Takeda described it as a particle, after which it said it conducted an emergency investigation.
Pollution reports also came from seven other vaccination centers, according to the Japan Times, and 390 doses - obtained have been affected.
