German police raided the headquarters of state-owned lender kfw this month as part of a criminal investigation into employees who approved an unsecured 100m loan to the collapsed payments group wirecard.

A spokesperson for kfw confirmed the raid, which happened two weeks ago, and said that the bank was co-operating with the investigation by frankfurt prosecutors.

Wirecards own headquarters on the outskirts of munich were raided by police on tuesday as part of the same investigation, according to people familiar with the matter. the police visit to wirecards base in aschheim was first reported by sddeutsche zeitung.

Kfw ipex bank, a subsidiary of the state-owned lender, in september 2018 agreed an unsecured loan over 100m to wirecard and then extended it last year. following wirecards collapse in june, kfw sold the loan to a distressed-debt investor, taking a huge but undisclosed loss.

The focus of the investigation is whether kfws decision to make and extend the loan may have been a breach of fiduciary duty, according to a spokesperson for the frankfurt prosecutors office.

Prosecutors confirmed that an investigation against staff of a frankfurt-based lender over an unsecured loan to wirecard was under way, but declined to identify the bank.

Wirecard is sitting on 3.2bn of loans that munich prosecutors investigating the companys collapse have concluded are most likely lost. for example, commerzbank, part of a consortium of 15 lenders who provided a 1.75bn revolving credit facility to wirecard, last month wrote off 97 per cent of its loan.

The group's munich-based administrator estimates that the defunct payments group's assets are worth less than 430m and several of its top executives are suspected of orchestrating a fraud that defrauded investors. markus braun, its former chief executive, denies allegations of fraud and embezzlement. jan marsalek, wirecards former second-in command, is on the run and wanted by police.

Munich prosecutors declined to comment on tuesdays raid at wirecards headquarters.