Italy's decision to ban a batch of AstraZeneca vaccine was taken following the deaths of two men in Sicily who had recently been inoculated, a source close to the matter said on Thursday.
Italy's medicines authority Aifa said earlier that the ban was a "precautionary" measure, adding that no link had been established between the vaccine and subsequent "serious adverse events."
The source said Aifa had moved after Stefano Paterno, a 43-year-old navy officer, died earlier this week of a suspected heart attack the day after his jab.
A second man, 50-year-old policeman Davide Villa, died last weekend, some 12 days after his jab. Local newspapers reported he fell ill within 24 hours of his injection and never recovered.
The source said both men had received shots from AstraZeneca's ABV2856 batch.