German energy giant Eon has vowed to contest a €38 million fine imposed by the European Commission yesterday for allegedly breaking a seal on a room containing seized documents.

The fine - a first in EU history - arises from an investigation launched by the commission's competition authority two years ago into allegations of illegal price-fixing in the Germany energy market.

"This decision sends a clear message to all companies that it does not pay to obstruct the commission's investigations," said European Commissioner for Competition Neelie Kroes.

Investigators raided the Munich offices of an Eon subsidiary on May 29th, 2006, and secured documents in a room.

Before going home for the evening, they placed a special plastic seal on the door which displays the word "void" if tampered with.

Investigators say this was the case when they returned the following morning, marking the beginning of a two-year legal battle with the German company.

"Eon claims not to be responsible for breaking the seal and first said that the investigators had the only key to the room," said a commission spokesman yesterday.

"Later it emerged that 20 other keys were in circulation among Eon employees."

Eon has put forward a variety of explanations for the voided seal including vibrations in the office walls, abrasive cleaning materials, air humidity and a fault in the seal itself.

"Nobody touched the seal and no files were missing from the sealed room," said an Eon spokesperson.