Graham Kelly, the FA's chief executive, said he was "bewildered" when the officials from Brussels burst into the offices at Lancaster Gate, west London, at 9.15am. But the FA denied last night it was involved in a multi-million-pound cartel covering the licensing of footballs that prompted similar raids at association headquarters in France and Denmark.
The visits were part of an investigation into the practice adopted by Fifa, football's world governing body, of insisting that only balls it has licensed are used in top matches. Sports manufacturers welcomed the swoop, arguing that the Fifa licensing costs amounted to about pounds 4.35 on the price of a football, but the English FA says that it receives none of the money.
The raids were conducted on behalf of Karel Van Miert, the European Competition Commissioner. A spokesman for his office said a complaint had been received a year ago from the World Federation of the Sporting Goods Industry which alleged that Fifa - and its affiliates, including the English FA - were violating the free and fair competition articles of the European Treaty.
According to the Commission, Fifa charges manufacturers 1 Swiss Franc (about 55p) to label its footballs "Fifa Inspected" and 2 Swiss Francs to label them "Fifa Approved", but it says other royalties and administrative costs push prices much higher.
Fifa insists all World Cup matches and qualifiers are played with such balls, arguing that is its prerogative because it owns the competition.
Its marketing partner, ISL Worldwide, said yesterday the agreement over footballs, reached in March last year, had already been reviewed by the European Commission and a preliminary investigation found no difficulties with it.
Mr Kelly said last night: "My response is to co-operate. I don't know what it is we are supposed to have done, but it's not a major issue."