An Italian unit of Amazon is being investigated by Milan prosecutors for suspected tax evasion, two sources said on Friday, but the inquiry was not linked to a multi-million euro seizure from another of the group's Italian units this week. Italy's tax police on Tuesday seized some 121 million euros ($131 million) from another unit of the U.S. e-retailer as part of an investigation into alleged tax fraud and illegal labour practices, prosecutors' documents showed. The second tax evasion investigation started in 2021 and was triggered by routine checks carried out by tax police in an area north of Milan, the two sources with knowledge of the matter said.