The arrests come after Britain's food regulator said that horsemeat tainted with an equine painkiller may have been sold to consumers for " some time."
Police in Britain has raided two meat production plants as a part of a growing Europe wide investigation into the sale of horse meat wrongly labeled as beef.
Thousands of genetic tests carried out across the European Union have found that almost 5% of processed beef products on sale have been contaminated with horsemeat.