About 100 accounts run by merchants who sell via Amazon were compromised by fraudsters, Bloomberg reported.

Quoting legal documents it had seen, Bloomberg said the fraudsters changed bank details on Amazon accounts to divert cash.

It is not known how much money the thieves managed to take.

Account check

The fraudsters were active between May and October 2018, said Bloomberg.

Amazon is still piecing together what happened during the long-running attack, but it believes targeted merchants were tricked into handing over login information for their accounts.

This high-level access would have let thieves change financial details and steal cash.

Tens of thousands of individuals and small firms use Amazon as their shop front to sell goods.

Cash generated by sales via Amazon, as well as loans advanced against future sales, are thought to have been taken by the thieves from accounts they targeted.

Amazon lawyers have asked for permission to search bank accounts held at Barclays and payment processing firm Prepay in a bid to track down the fraudsters, said Bloomberg.

It said the two firms had "become innocently mixed up in the wrongdoing".