Dozens of people have been arrested in the Netherlands and in Italy in connection with a major fraud involving Dutch flower firms, the Parool reported on Tuesday.

Three of those picked up are Italian brothers aged 42, 50 and 52, who live in Aalsmeer and worked at the town’s massive flower auction. They are members of an Italian crime family, the paper said.

The gang is said to have been operating for years. They first bought small quantities of flowers from Dutch growers which they paid for quickly. After winning the growers’ and transport firms’ trust, they began to place much bigger orders in the run up to Italian holidays, the Parool said. To avoid paying, they had their companies declared bankrupt.

So far, 10 Dutch growers have made formal complaints about being scammed. Some have lost tens of thousands of euros but others up to €2m, the paper said. Several have also gone out of business.

The investigation so far has taken six months. Dutch police were alerted by their Italian counterparts when they came across a plot to murder someone who worked at the Aalsmeer auction house.