European Union antitrust regulators have raided the offices of several companies that make and sell consumer electronics and domestic appliances online, in an investigation into whether they artificially boosting the prices of goods online.

Royal Philips NV confirmed Friday it was one of the companies "visited" by representatives of the European Commission, the EU's executive arm. Spokesman Joost Akkermans says the company is cooperating with an "ongoing case" but it cannot comment further.

The Commission said it has reason to believe companies involved may have restricted online sales of their products to keep their prices high or made them unavailable at outlets that sold them cheaply.

It underlined that its investigation is at a prelimary stage and may never lead to charges, let alone a finding of guilt.