Italian middlemen allegedly pocketed €70 million (£60 million) in illicit "commissions" from Chinese companies in return for helping to negotiate contracts for Italy to buy €1.25 billion worth of face masks.
Eight people are under investigation for the allegedly corrupt deal, which took place last spring, just as Italy was hit by the first wave of the pandemic.
Italian police seized €70 million worth of their assets, from bank accounts and property to designer watches worth €10,000 each and a Tiffany's necklace valued at €14,000.
The seizures also included a yacht worth €770,000 and a Harley Davidson motorcycle, which prosecutors believe were bought with the proceeds of the deals.
Finance police suspect the group of skimming millions of euros off contracts for the procurement of more than 800 million masks from three Chinese consortiums.
They are accused of money laundering, influence peddling and trading in stolen goods.
The contracts were signed off by Domenico Arcuri, Italy's coronavirus crisis commissioner, but police said he had no involvement in the alleged corruption.
His office said in a statement that he had been the victim of "illicit manipulation" and that he was "extraneous" to the allegations.
He will cooperate fully with the investigation and his lawyers said he might take legal action against the alleged brokers.
Chinese businesses paid the huge bribes in return for "preferential access" to government tender processes, investigators allege. The investigation had revealed "the avarice and unscrupulousness of the protagonists in this affair," prosecutors said.
Since Italy became the first Western country to be engulfed by the Covid-19 pandemic, nearly 95,000 people have died.
Businesses have closed, hundreds of thousands of people have lost their jobs and GDP has shrunk by nearly nine per cent - the most drastic contraction since the Second World War.
The country's 20 regions remain in varying degrees of lockdown. Across the whole of Italy there is a 10pm-5am curfew and travel between regions is banned unless for essential reasons.