Details of loans made by collapsed Icelandic bank Kaupthing to a company owned by retail entrepreneur Kevin Stanford have been passed to criminal investigators in Iceland.

There is no suggestion of illegality on the part of Stanford or his companies – he had stakes in retailers including All Saints and House of Fraser.

The allegations centre on concerns about potential market manipulation involving Kaupthing derivative transactions, The Guardian newspaper reported.

The development illustrates how high-profile entrepreneurs may have been “drawn into a labyrinthine web of poorly collateralised loans and cross-investments that increasingly came to characterise the dangerously outsized Icelandic banking system in the years before the meltdown” the newspaper said.

Stanford was one of Kaupthing’s biggest customers, with borrowings of €519m as at September last year. He was also the fourth largest investor in Kaupthing.

Stanford’s retail holdings are understood to have been taken back by the bank.