Statoil says that European antitrust officials have inspected its head office on suspicion of the Norwegian oil company's participation in anti-competitive practices.

The inspection, at Statoil's headquarters in Stavanger, Norway, was at the request of the European Union's executive, the Commission, and carried out with the assistance of Norwegian antitrust officials. Norway is not a member of the EU.

The Commission said in a statement Tuesday that it had requested raids on several oil-sector companies on concerns that they "may have colluded in reporting distorted prices" and "prevented others from participating in the price assessment process, with a view to distorting published prices". It did not identify the companies involved.

Statoil officials could not immediately be reached for comment. The company said it is "cooperating with the authorities."