Police from seven European countries have arrested 26 people in a crackdown on a horse meat trafficking ring two years after a tainted meat scandal that rocked the European Union.

The Department of Agriculture has confirmed that its department vets along with gardaí took part in the initiative.

The EU's judicial agency Eurojust said in a statement that the swoop gathering hundreds of police and judicial officials "succeeded in stopping an organised criminal network involved in trade in illegal horse meat."

The operation involved officers and the judiciary in France, Belgium, Germany, Ireland, Luxembourg, the Netherlands and Britain, the European Union agency said.

Eurojust did not say where the 26 suspects were arrested but the Dutch public prosecutor's office said three were arrested in the Netherlands.

France had requested the trio's extradition, the prosecutors added.

Media in Belgium said four of its nationals, including the alleged ringleader, were arrested in France.

Eurojust said the main suspect in the ring, which is accused of introducing horse meat unfit for human consumption into the European food chain, was Belgian.

The suspect, who was operating out of Belgium, had been under investigation since November 2012, the statement added.

French authorities estimate that between 2010 and 2013 some 4,700 horses unfit for human consumption were slaughtered for the food trade, Eurojust said.

Dozens of commercial and private premises were searched in the raids and more than 800 horse passports seized along with medication, microchips and computer equipment.

The arrests come two years after a major scandal triggered by the discovery that horsemeat was being passed off as beef in burgers and other meat products sold across Europe.

Meatballs, sausages and frozen burgers were pulled from supermarket shelves by the millions over the find.

Eurojust did not say whether there was any connection between this week's raids and the 2013 horsemeat scandal.