Some 70 Dutch amateur football clubs say they have evidence that criminals have been trying to infiltrate their organisations, RTL Nieuws said on Thursday.

The broadcaster bases its claim on a survey of 386 amateur clubs and found many are concerned about being offered cash money by dubious sponsors and sponsors who want to remain anonymous.

Groningen club VVK, which is in financial trouble, told RTL that it had turned down a sponsorship deal because it was concerned about the origin of the sponsor’s money.

Another club, which wanted to remain anonymous said: ‘We have one sponsor who only wants to pay cash. We’ve got our doubts about it, but it is very hard to stand up to him.’

Clubs which do end up taking dodgy cash can themselves end up in trouble, RTL said. It referred to Haarlem club Young Boys which went bust after one sponsor organised an illegal poker tournament in the club canteen.

Sports lawyer and professor Marjan Olfers said that criminals hope to either buy influence or launder money by getting involved in sport sponsorship. ‘If you put a lot of money in a club and it moves up a division or two, then that has a great impact on your reputation,’ she said.

The KNVB told RTL that it is not convinced the problem is as serious as is being made out. In addition, the KNVB is a ‘sports association not a detective agency’, a spokesman said.

Nevertheless, clubs which are in trouble can approach one of the KNVB’s 18 special advisors for help, the spokesman said. In addition, the organisation hopes local authorities and the police will start an investigation to tackle the problem.

MPs have called on the government to take the problem seriously, following the RTL report.