In Ferrara's account, five bombs were dropped, of which one did not explode. According to the Actes et documents du Saint Siège relatifs à la seconde guerre mondiale,[14] the report of an examination carried out by Vatican authorities after the event spoke only of fragments that made it difficult to determine whether the high-explosive bombs, which had been of 100–150 kg weight and produced small craters over a wide range, were of British, German or Italian manufacture.