German prosecutors and tax authorities searched the offices of the German Football Association (DFB), as well as the private homes of current and former officials on suspicion of serious tax evasion, the Frankfurt prosecutors' office, said Wednesday.

It said six former and current officials of the DFB were suspected of having intentionally falsely declared income from advertising inside football stadiums during certain matches in 2014 and 2015 as income from asset management, leading to an evasion of 4.7 million euros ($5.52 million) worth of taxes.

The DFB, which does not pay taxes for any income made from asset management but is obliged to do so for earnings from any commercial activities, did not respond to Reuters requests for comment.

Some 200 police officers searched the DFB's Frankfurt headquarters and the homes of officials in five federal states, prosecutors said, without identifying the six suspects.

Based on the investigation until now, there is the suspicion that those accused knew of the tax incorrectness but consciously did it to give the DFB a major tax advantage.

The DFB said in June it was ending its partnership with marketing company Infront in connection with alleged corruption after a report from a consultancy revealed "clear irregularities in connection with the creation and provision of contractual services by Infront, as well as unlawful interference with DFB representatives."

Until 2018, Infront was commissioned to procure advertising board partners for national team games. According to the consultancy report, Infront got the contract in 2013 even though another company offered 18 million euros more.

A similar and still valid contract for German Cup games is also said to have been given to Infront in 2015 under dubious circumstances.

Infront has denied any wrongdoing.

This is the latest in a series of legal cases that have tarnished the world's biggest soccer federation, which was also under investigation for the suspected misuse of funds for the 2006 World Cup hosted in Germany.

Theo Zwanziger, DFB head from 2006-2012, and his successor Wolfgang Niersbach were investigated for years in Germany and Switzerland over the allegations, with both men denying any wrongdoing. Niersbach resigned in 2015 over the 2006 scandal.

His successor, Reinhard Grindel, who was president from 2016-2019 and DFB treasurer between 2013-2015, also resigned in 2019 over a gold watch he received as a gift during a meeting of the European football body, UEFA.