Dutch meat wholesaler Willy Selten was arrested on Thursday for allegedly selling 300 tonnes of horsemeat labelled as beef, the public prosecutor said.
"The director and the interim director have been arrested," a statement said. "They are suspected of false accounting and fraud."
The prosecutor's office said that Dutch food safety authority NVWA arrested the man as part of "a criminal investigation into labelling horsemeat as beef."
The statement said the man's company was the same as the one searched as part of an initial probe when Europe's adulterated beef scandal erupted in February.
Dutch media reported that the man was Selten.
Selten, allegedly a key player in Europe's horsemeat scandal, in April failed to quash an order recalling 50,000 tonnes of potentially contaminated horsemeat that had passed through his plant in the southern Dutch city of Oss.
The NVWA asked hundreds of companies across Europe supplied by Selten to check their products.
Selten's company was last month also declared bankrupt and placed under curatorship.
"The business allegedly received 300 tonnes of horsemeat from the Netherlands, England and Ireland in 2011 and 2012," the prosecutor said on Thursday.
An investigation showed that this horsemeat was processed as beef according to the company's accounts, which said that the business only sold beef, the statement said.